Merge pull request #55 from dmnyc/feat/collapsible-threads

feat: collapsible reply threads + iOS-parity UI polish

app/src/main/kotlin/com/darkwisp/app/ui/component/CollapsedRepliesRow.kt

@@ -0,0 +1,58 @@
+package com.darkwisp.app.ui.component
+
+import androidx.compose.foundation.clickable
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.Spacer
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.layout.width
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.filled.KeyboardArrowDown
+import androidx.compose.material3.Icon
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.res.pluralStringResource
+import androidx.compose.ui.unit.dp
+import com.darkwisp.app.R
+import com.darkwisp.app.viewmodel.thread.ThreadItem
+
+/**
+ * Folded-subtree affordance: "Show N more replies". Tapping expands the subtree inline — the
+ * caller's [onExpand] handles the VM toggle (and scroll anchoring, where used). The guide rail
+ * is dashed at the top to signal it continues upward to the anchor note. Shared by ThreadScreen
+ * and ArticleScreen so the two progressive-disclosure surfaces stay consistent.
+ */
+@Composable
+fun CollapsedRepliesRow(
+    item: ThreadItem.CollapsedReplies,
+    onExpand: () -> Unit,
+    modifier: Modifier = Modifier
+) {
+    val indent = threadIndentDp(item.depth)
+    val lineColor = MaterialTheme.colorScheme.outlineVariant.copy(alpha = 0.5f)
+    Row(
+        modifier = modifier
+            .fillMaxWidth()
+            .threadConnector(show = true, indent = indent, lineColor = lineColor, dashedTop = true)
+            .clickable(onClick = onExpand)
+            .padding(start = indent, top = 8.dp, bottom = 8.dp, end = 12.dp),
+        verticalAlignment = Alignment.CenterVertically
+    ) {
+        Icon(
+            imageVector = Icons.Filled.KeyboardArrowDown,
+            contentDescription = null,
+            modifier = Modifier.size(16.dp),
+            tint = MaterialTheme.colorScheme.primary
+        )
+        Spacer(Modifier.width(6.dp))
+        Text(
+            text = pluralStringResource(R.plurals.thread_continue, item.hiddenCount, item.hiddenCount),
+            style = MaterialTheme.typography.labelMedium,
+            color = MaterialTheme.colorScheme.primary
+        )
+    }
+}

app/src/main/kotlin/com/darkwisp/app/ui/component/GalleryCard.kt

@@ -323,21 +323,27 @@ fun GalleryCard(
             )
             Spacer(Modifier.width(10.dp))
             Column(modifier = Modifier.weight(1f)) {
-                Text(
-                    text = displayName,
-                    style = MaterialTheme.typography.titleMedium,
-                    color = MaterialTheme.colorScheme.onSurface,
-                    maxLines = 1,
-                    overflow = TextOverflow.Ellipsis,
-                    modifier = Modifier.clickable(onClick = onProfileClick)
-                )
-                profile?.nip05?.let { nip05 ->
-                    Nip05Badge(
-                        nip05 = nip05,
-                        pubkey = event.pubkey,
-                        nip05Repo = nip05Repo,
-                        onClick = onProfileClick
+                Row(verticalAlignment = Alignment.CenterVertically) {
+                    Text(
+                        text = displayName,
+                        style = MaterialTheme.typography.titleMedium,
+                        color = MaterialTheme.colorScheme.onSurface,
+                        maxLines = 1,
+                        overflow = TextOverflow.Ellipsis,
+                        modifier = Modifier
+                            .weight(1f, fill = false)
+                            .clickable(onClick = onProfileClick)
                     )
+                    profile?.nip05?.let { nip05 ->
+                        Spacer(Modifier.width(4.dp))
+                        Nip05Badge(
+                            nip05 = nip05,
+                            pubkey = event.pubkey,
+                            nip05Repo = nip05Repo,
+                            onClick = onProfileClick,
+                            showHandle = false
+                        )
+                    }
                 }
             }
             Text(
@@ -933,7 +939,7 @@ private fun formatGalleryTimestamp(epoch: Long): String {
     if (hours < 24) return "${hours}h"
 
     val days = diff / (24 * 60 * 60 * 1000L)
-    if (days == 1L) return "yesterday"
+    if (days < 7) return "${days}d"
 
     val date = Date(millis)
     val cal = java.util.Calendar.getInstance()

app/src/main/kotlin/com/darkwisp/app/ui/component/PostCard.kt

@@ -21,6 +21,7 @@ import androidx.compose.foundation.layout.offset
 import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.layout.width
 import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.automirrored.outlined.Reply
 import androidx.compose.material.icons.filled.KeyboardArrowDown
 import androidx.compose.material.icons.filled.KeyboardArrowUp
 import androidx.compose.material.icons.filled.MoreVert
@@ -60,7 +61,7 @@ import androidx.compose.ui.unit.dp
 import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.zIndex
 import androidx.compose.foundation.layout.size
-import androidx.compose.material.icons.filled.CheckCircle
+import androidx.compose.material.icons.filled.Verified
 import androidx.compose.material.icons.filled.Cancel
 import androidx.compose.material.icons.filled.Check
 import androidx.compose.material.icons.filled.Close
@@ -289,6 +290,27 @@ fun PostCard(
                 }
             }
         }
+        if (replyToName != null) {
+            Row(
+                verticalAlignment = Alignment.CenterVertically,
+                modifier = Modifier.padding(bottom = 4.dp)
+            ) {
+                Icon(
+                    imageVector = Icons.AutoMirrored.Outlined.Reply,
+                    contentDescription = null,
+                    modifier = Modifier.size(14.dp),
+                    tint = MaterialTheme.colorScheme.onSurfaceVariant
+                )
+                Spacer(Modifier.width(6.dp))
+                Text(
+                    text = stringResource(R.string.post_replying_to, replyToName),
+                    style = MaterialTheme.typography.bodySmall,
+                    color = MaterialTheme.colorScheme.onSurfaceVariant,
+                    maxLines = 1,
+                    overflow = TextOverflow.Ellipsis
+                )
+            }
+        }
         Row(verticalAlignment = Alignment.CenterVertically) {
             ProfilePicture(
                 url = profile?.picture,
@@ -298,30 +320,25 @@ fun PostCard(
             )
             Spacer(Modifier.width(10.dp))
             Column(modifier = Modifier.weight(1f)) {
-                Text(
-                    text = displayName,
-                    style = MaterialTheme.typography.titleMedium,
-                    color = MaterialTheme.colorScheme.onSurface,
-                    maxLines = 1,
-                    overflow = TextOverflow.Ellipsis,
-                    modifier = Modifier.clickable(onClick = onProfileClick)
-                )
-                if (replyToName != null) {
-                    Row(verticalAlignment = Alignment.CenterVertically) {
-                        Text(
-                            text = "replying to ",
-                            style = MaterialTheme.typography.bodySmall,
-                            color = MaterialTheme.colorScheme.onSurfaceVariant
-                        )
-                        Text(
-                            text = replyToName,
-                            style = MaterialTheme.typography.bodySmall,
-                            color = MaterialTheme.colorScheme.primary,
-                            maxLines = 1,
-                            overflow = TextOverflow.Ellipsis,
-                            modifier = Modifier.clickable {
-                                replyToPubkey?.let { onNavigateToProfile?.invoke(it) }
-                            }
+                Row(verticalAlignment = Alignment.CenterVertically) {
+                    Text(
+                        text = displayName,
+                        style = MaterialTheme.typography.titleMedium,
+                        color = MaterialTheme.colorScheme.onSurface,
+                        maxLines = 1,
+                        overflow = TextOverflow.Ellipsis,
+                        modifier = Modifier
+                            .weight(1f, fill = false)
+                            .clickable(onClick = onProfileClick)
+                    )
+                    profile?.nip05?.let { nip05 ->
+                        Spacer(Modifier.width(4.dp))
+                        Nip05Badge(
+                            nip05 = nip05,
+                            pubkey = event.pubkey,
+                            nip05Repo = nip05Repo,
+                            onClick = onProfileClick,
+                            showHandle = false
                         )
                     }
                 }
@@ -340,14 +357,6 @@ fun PostCard(
                         fontStyle = androidx.compose.ui.text.font.FontStyle.Italic
                     )
                 }
-                profile?.nip05?.let { nip05 ->
-                    Nip05Badge(
-                        nip05 = nip05,
-                        pubkey = event.pubkey,
-                        nip05Repo = nip05Repo,
-                        onClick = onProfileClick
-                    )
-                }
             }
             if (isPrivate) {
                 Icon(
@@ -1261,7 +1270,7 @@ private val dateTimeYearFormat = SimpleDateFormat("MMM d, yyyy", Locale.US)
 
 /**
  * Format an epoch timestamp into a relative or absolute time string.
- * Avoids Calendar allocations — uses simple arithmetic for "yesterday" check.
+ * Avoids Calendar allocations for the s/m/h/d tiers — simple arithmetic.
  */
 private fun formatTimestamp(epoch: Long): String {
     val now = System.currentTimeMillis()
@@ -1279,7 +1288,7 @@ private fun formatTimestamp(epoch: Long): String {
     if (hours < 24) return "${hours}h"
 
     val days = diff / (24 * 60 * 60 * 1000L)
-    if (days == 1L) return "yesterday"
+    if (days < 7) return "${days}d"
 
     val date = Date(millis)
     val cal = java.util.Calendar.getInstance()
@@ -1307,6 +1316,10 @@ internal fun Nip05Badge(
     onClick: (() -> Unit)? = null,
     maxLines: Int = 1,
     verifiedTint: Color = MaterialTheme.colorScheme.primary,
+    /** When false, render only the verification icon — no handle text. The handle itself
+     *  is reserved for the profile screen; everywhere else (feed, threads, comments) just
+     *  the badge icon appears next to the username. */
+    showHandle: Boolean = true,
     modifier: Modifier = Modifier
 ) {
     if (nip05.isBlank()) return
@@ -1335,6 +1348,25 @@ internal fun Nip05Badge(
             }
         )
     ) {
+        if (!showHandle) {
+            // Icon-only badge: appears once verification resolves. No retry icon here —
+            // a transient relay error shouldn't flag every row across the timeline.
+            when {
+                status == Nip05Status.VERIFIED -> Icon(
+                    Icons.Default.Verified,
+                    contentDescription = "Verified",
+                    tint = verifiedTint,
+                    modifier = Modifier.size(14.dp)
+                )
+                isImpersonator -> Icon(
+                    Icons.Default.Cancel,
+                    contentDescription = "Impersonator",
+                    tint = Color.Red,
+                    modifier = Modifier.size(14.dp)
+                )
+            }
+            return@Row
+        }
         Text(
             text = nip05,
             style = MaterialTheme.typography.bodySmall,
@@ -1346,7 +1378,7 @@ internal fun Nip05Badge(
         if (status == Nip05Status.VERIFIED) {
             Spacer(Modifier.width(4.dp))
             Icon(
-                Icons.Default.CheckCircle,
+                Icons.Default.Verified,
                 contentDescription = "Verified",
                 tint = verifiedTint,
                 modifier = Modifier.size(14.dp)

app/src/main/kotlin/com/darkwisp/app/ui/component/ProfilePicture.kt

@@ -28,6 +28,7 @@ import androidx.compose.ui.draw.drawBehind
 import androidx.compose.ui.geometry.Offset
 import androidx.compose.ui.graphics.Brush
 import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.graphics.luminance
 import androidx.compose.ui.graphics.graphicsLayer
 import androidx.compose.ui.hapticfeedback.HapticFeedbackType
 import androidx.compose.ui.layout.ContentScale
@@ -196,6 +197,10 @@ private fun BaseProfilePicture(
 @Composable
 private fun FollowBadge(size: Int, modifier: Modifier = Modifier) {
     val badgeSize = (size * 0.3f).coerceIn(10f, 16f)
+    // iOS parity: the check flips with the color scheme — black on the
+    // orange circle in dark mode, white in light mode. Derive from the
+    // active surface so theme presets stay correct too.
+    val checkColor = if (MaterialTheme.colorScheme.surface.luminance() < 0.5f) Color.Black else Color.White
     Box(
         contentAlignment = Alignment.Center,
         modifier = modifier
@@ -207,7 +212,7 @@ private fun FollowBadge(size: Int, modifier: Modifier = Modifier) {
         Icon(
             Icons.Default.Check,
             contentDescription = "Following",
-            tint = MaterialTheme.colorScheme.onPrimary,
+            tint = checkColor,
             modifier = Modifier.size((badgeSize * 0.65f).dp)
         )
     }

app/src/main/kotlin/com/darkwisp/app/ui/component/RichContent.kt

@@ -1359,15 +1359,28 @@ fun QuotedNote(
                 Row(verticalAlignment = Alignment.CenterVertically) {
                     ProfilePicture(url = profile?.picture, size = 34)
                     Spacer(Modifier.width(10.dp))
-                    Column(modifier = Modifier.weight(1f)) {
+                    Row(
+                        verticalAlignment = Alignment.CenterVertically,
+                        modifier = Modifier.weight(1f)
+                    ) {
                         Text(
                             text = profile?.displayString
                                 ?: event.pubkey.take(8) + "..." + event.pubkey.takeLast(4),
                             style = MaterialTheme.typography.titleSmall,
                             color = MaterialTheme.colorScheme.onSurface,
                             maxLines = 1,
-                            overflow = TextOverflow.Ellipsis
+                            overflow = TextOverflow.Ellipsis,
+                            modifier = Modifier.weight(1f, fill = false)
                         )
+                        profile?.nip05?.let { nip05 ->
+                            Spacer(Modifier.width(4.dp))
+                            Nip05Badge(
+                                nip05 = nip05,
+                                pubkey = event.pubkey,
+                                nip05Repo = noteActions?.nip05Repo,
+                                showHandle = false
+                            )
+                        }
                     }
                     Text(
                         text = formatQuotedTimestamp(event.created_at),
@@ -2000,7 +2013,7 @@ private fun formatQuotedTimestamp(epoch: Long): String {
         seconds < 60 -> "${seconds}s"
         minutes < 60 -> "${minutes}m"
         hours < 24 -> "${hours}h"
-        days == 1L -> "yesterday"
+        days < 7 -> "${days}d"
         else -> java.text.SimpleDateFormat("MMM d", java.util.Locale.US).format(java.util.Date(epoch * 1000))
     }
 }

app/src/main/kotlin/com/darkwisp/app/ui/component/ThreadIndent.kt

@@ -0,0 +1,103 @@
+package com.darkwisp.app.ui.component
+
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.draw.drawBehind
+import androidx.compose.ui.geometry.Offset
+import androidx.compose.ui.geometry.Size
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.graphics.Paint
+import androidx.compose.ui.graphics.PaintingStyle
+import androidx.compose.ui.graphics.PathEffect
+import androidx.compose.ui.graphics.StrokeCap
+import androidx.compose.ui.graphics.drawscope.Stroke
+import androidx.compose.ui.graphics.drawscope.drawIntoCanvas
+import androidx.compose.ui.unit.Dp
+import androidx.compose.ui.unit.dp
+import com.darkwisp.app.viewmodel.thread.ThreadFlattener
+import kotlin.math.min
+
+/** Per-level indent step for threaded replies. */
+private val INDENT_STEP: Dp = 16.dp
+
+/**
+ * Start-padding indent for a reply at [depth], clamped to the thread depth cap so the rail
+ * never runs out of horizontal space.
+ */
+fun threadIndentDp(depth: Int, cap: Int = ThreadFlattener.DEPTH_CAP, step: Dp = INDENT_STEP): Dp =
+    step * min(depth, cap)
+
+/**
+ * Depth connector: a single vertical rail into a rounded corner and a short horizontal run to
+ * the reply — instead of one straight line per ancestor level. Drawn behind a row when [show]
+ * is true (depth > 0). [indent] is the row's start padding (from [threadIndentDp]); the rail
+ * lands one corner radius left of the card's padded edge so the arc's horizontal run meets the
+ * card edge exactly.
+ *
+ * When [dashedTop] is true the top of the rail is drawn dashed, signalling that the guide line
+ * continues upward to a parent that isn't the row directly above (e.g. the first reply of a
+ * branch, or a reply revealed by expanding a folded subtree) — so the rail doesn't look like it
+ * starts "in mid-air."
+ *
+ * Shared by ThreadScreen and ArticleScreen so the two indent paths can't drift.
+ */
+fun Modifier.threadConnector(
+    show: Boolean,
+    indent: Dp,
+    lineColor: Color,
+    cornerRadius: Dp = 8.dp,
+    stroke: Dp = 1.dp,
+    dashedTop: Boolean = false,
+    dashLength: Dp = 14.dp
+): Modifier = this.drawBehind {
+    if (!show) return@drawBehind
+    val r = cornerRadius.toPx()
+    val strokePx = stroke.toPx()
+    val lineX = indent.toPx() - r + strokePx
+    val railBottom = size.height - r
+
+    if (dashedTop && railBottom > 0f) {
+        val dashEnd = min(railBottom, dashLength.toPx())
+        val dashOn = (stroke * 3).toPx()
+        val dashOff = (stroke * 3).toPx()
+        drawIntoCanvas { canvas ->
+            val paint = Paint().apply {
+                color = lineColor
+                strokeWidth = strokePx
+                style = PaintingStyle.Stroke
+                pathEffect = PathEffect.dashPathEffect(floatArrayOf(dashOn, dashOff), 0f)
+                isAntiAlias = true
+            }
+            canvas.drawLine(Offset(lineX, 0f), Offset(lineX, dashEnd), paint)
+        }
+        if (dashEnd < railBottom) {
+            drawLine(
+                color = lineColor,
+                start = Offset(lineX, dashEnd),
+                end = Offset(lineX, railBottom),
+                strokeWidth = strokePx
+            )
+        }
+    } else {
+        drawLine(
+            color = lineColor,
+            start = Offset(lineX, 0f),
+            end = Offset(lineX, railBottom),
+            strokeWidth = strokePx
+        )
+    }
+    drawArc(
+        color = lineColor,
+        startAngle = 90f,
+        sweepAngle = 90f,
+        useCenter = false,
+        topLeft = Offset(lineX, size.height - 2f * r),
+        size = Size(2f * r, 2f * r),
+        style = Stroke(width = strokePx, cap = StrokeCap.Round)
+    )
+    drawLine(
+        color = lineColor,
+        start = Offset(lineX + r, size.height),
+        end = Offset(size.width, size.height),
+        strokeWidth = strokePx
+    )
+}

app/src/main/kotlin/com/darkwisp/app/ui/screen/ArticleScreen.kt

@@ -16,6 +16,7 @@ import androidx.compose.foundation.layout.height
 import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.layout.width
 import androidx.compose.foundation.lazy.LazyColumn
+import androidx.compose.foundation.lazy.items
 import androidx.compose.foundation.rememberScrollState
 import androidx.compose.foundation.shape.RoundedCornerShape
 import androidx.compose.material.icons.Icons
@@ -64,8 +65,11 @@ import com.darkwisp.app.ui.component.ActionBar
 import com.darkwisp.app.ui.component.NoteActions
 import com.darkwisp.app.ui.component.PostCard
 import com.darkwisp.app.ui.component.RichContent
+import com.darkwisp.app.ui.component.CollapsedRepliesRow
+import com.darkwisp.app.ui.component.threadConnector
+import com.darkwisp.app.ui.component.threadIndentDp
 import com.darkwisp.app.viewmodel.ArticleViewModel
-import kotlin.math.min
+import com.darkwisp.app.viewmodel.thread.ThreadItem
 
 @OptIn(ExperimentalMaterial3Api::class, ExperimentalLayoutApi::class)
 @Composable
@@ -355,51 +359,73 @@ fun ArticleScreen(
                     }
 
                     // Comment items
-                    items(comments.size, key = { "comment-${comments[it].first.id}" }) { index ->
-                        val (event, depth) = comments[index]
-                        val commentProfile = remember(profileVersion, event.pubkey) { eventRepo.getProfileData(event.pubkey) }
-                        val commentLikeCount = remember(reactionVersion, event.id) { eventRepo.getReactionCount(event.id) }
-                        val commentReplyCount = remember(replyCountVersion, event.id) { eventRepo.getReplyCount(event.id) }
-                        val commentZapSats = remember(zapVersion, event.id) { eventRepo.getZapSats(event.id) }
-                        val commentUserEmojis = remember(reactionVersion, event.id, userPubkey) {
-                            userPubkey?.let { eventRepo.getUserReactionEmojis(event.id, it) } ?: emptySet()
+                    items(items = comments, key = { "comment_${it.key}" }, contentType = { "comment" }) { item ->
+                        if (item !is ThreadItem.Post) {
+                            // Folded comment subtree — expand inline.
+                            if (item is ThreadItem.CollapsedReplies) {
+                                CollapsedRepliesRow(
+                                    item = item,
+                                    onExpand = { viewModel.expandBranch(item.anchor.id) },
+                                    modifier = Modifier.animateItem()
+                                )
+                            }
+                        } else {
+                            val event = item.event
+                            val commentProfile = remember(profileVersion, event.pubkey) { eventRepo.getProfileData(event.pubkey) }
+                            val commentLikeCount = remember(reactionVersion, event.id) { eventRepo.getReactionCount(event.id) }
+                            val commentReplyCount = remember(replyCountVersion, event.id) { eventRepo.getReplyCount(event.id) }
+                            val commentZapSats = remember(zapVersion, event.id) { eventRepo.getZapSats(event.id) }
+                            val commentUserEmojis = remember(reactionVersion, event.id, userPubkey) {
+                                userPubkey?.let { eventRepo.getUserReactionEmojis(event.id, it) } ?: emptySet()
+                            }
+                            val commentRepostCount = remember(repostVersion, event.id) { eventRepo.getRepostCount(event.id) }
+                            val commentHasUserReposted = remember(repostVersion, event.id) { eventRepo.hasUserReposted(event.id) }
+                            val commentHasUserZapped = remember(zapVersion, event.id) { eventRepo.hasUserZapped(event.id) }
+                            val commentReactionEmojiUrls = remember(reactionVersion, event.id) { eventRepo.getReactionEmojiUrls(event.id) }
+                            val indent = threadIndentDp(item.depth)
+                            val lineColor = MaterialTheme.colorScheme.outlineVariant.copy(alpha = 0.5f)
+                            PostCard(
+                                event = event,
+                                profile = commentProfile,
+                                onReply = { onReply(event) },
+                                onProfileClick = { onProfileClick(event.pubkey) },
+                                onNavigateToProfile = onProfileClick,
+                                onNoteClick = {},
+                                onReact = { emoji -> onReact(event, emoji) },
+                                userReactionEmojis = commentUserEmojis,
+                                onRepost = { onRepost(event) },
+                                onQuote = { onQuote(event) },
+                                hasUserReposted = commentHasUserReposted,
+                                repostCount = commentRepostCount,
+                                onZap = { onZap(event) },
+                                onZapLongPress = { onZapInstant(event) },
+                                hasUserZapped = commentHasUserZapped,
+                                likeCount = commentLikeCount,
+                                replyCount = commentReplyCount,
+                                zapSats = commentZapSats,
+                                isZapAnimating = event.id in zapAnimatingIds,
+                                isZapInProgress = event.id in zapInProgressIds,
+                                eventRepo = eventRepo,
+                                reactionEmojiUrls = commentReactionEmojiUrls,
+                                resolvedEmojis = resolvedEmojis,
+                                unicodeEmojis = unicodeEmojis,
+                                onOpenEmojiLibrary = onOpenEmojiLibrary,
+                                isOwnEvent = event.pubkey == userPubkey,
+                                onAddToList = { onAddToList(event.id) },
+                                isInList = event.id in listedIds,
+                                noteActions = noteActions,
+                                modifier = Modifier
+                                    .fillMaxWidth()
+                                    .animateItem()
+                                    .threadConnector(
+                                        show = item.depth > 0,
+                                        indent = indent,
+                                        lineColor = lineColor,
+                                        dashedTop = item.connectorStartsMidAir
+                                    )
+                                    .padding(start = indent)
+                            )
                         }
-                        val commentRepostCount = remember(repostVersion, event.id) { eventRepo.getRepostCount(event.id) }
-                        val commentHasUserReposted = remember(repostVersion, event.id) { eventRepo.hasUserReposted(event.id) }
-                        val commentHasUserZapped = remember(zapVersion, event.id) { eventRepo.hasUserZapped(event.id) }
-                        val commentReactionEmojiUrls = remember(reactionVersion, event.id) { eventRepo.getReactionEmojiUrls(event.id) }
-                        PostCard(
-                            event = event,
-                            profile = commentProfile,
-                            onReply = { onReply(event) },
-                            onProfileClick = { onProfileClick(event.pubkey) },
-                            onNavigateToProfile = onProfileClick,
-                            onNoteClick = {},
-                            onReact = { emoji -> onReact(event, emoji) },
-                            userReactionEmojis = commentUserEmojis,
-                            onRepost = { onRepost(event) },
-                            onQuote = { onQuote(event) },
-                            hasUserReposted = commentHasUserReposted,
-                            repostCount = commentRepostCount,
-                            onZap = { onZap(event) },
-                            onZapLongPress = { onZapInstant(event) },
-                            hasUserZapped = commentHasUserZapped,
-                            likeCount = commentLikeCount,
-                            replyCount = commentReplyCount,
-                            zapSats = commentZapSats,
-                            isZapAnimating = event.id in zapAnimatingIds,
-                            isZapInProgress = event.id in zapInProgressIds,
-                            eventRepo = eventRepo,
-                            reactionEmojiUrls = commentReactionEmojiUrls,
-                            resolvedEmojis = resolvedEmojis,
-                            unicodeEmojis = unicodeEmojis,
-                            onOpenEmojiLibrary = onOpenEmojiLibrary,
-                            isOwnEvent = event.pubkey == userPubkey,
-                            onAddToList = { onAddToList(event.id) },
-                            isInList = event.id in listedIds,
-                            noteActions = noteActions,
-                            modifier = Modifier.padding(start = (min(depth, 4) * 24).dp)
-                        )
                     }
 
                     item(key = "footer") { Spacer(Modifier.height(32.dp)) }

app/src/main/kotlin/com/darkwisp/app/ui/screen/NotificationsScreen.kt

@@ -2255,7 +2255,7 @@ private fun formatNotifTimestamp(epoch: Long): String {
     if (hours < 24) return "${hours}h"
 
     val days = diff / (24 * 60 * 60 * 1000L)
-    if (days == 1L) return "yesterday"
+    if (days < 7) return "${days}d"
 
     val date = Date(millis)
     val cal = java.util.Calendar.getInstance()

app/src/main/kotlin/com/darkwisp/app/ui/screen/ThreadScreen.kt

@@ -51,11 +51,6 @@ import androidx.compose.foundation.lazy.rememberLazyListState
 import androidx.compose.runtime.rememberCoroutineScope
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
-import androidx.compose.ui.draw.drawBehind
-import androidx.compose.ui.geometry.Offset
-import androidx.compose.ui.geometry.Size
-import androidx.compose.ui.graphics.StrokeCap
-import androidx.compose.ui.graphics.drawscope.Stroke
 import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.ui.platform.LocalContext
 import androidx.compose.ui.unit.dp
@@ -68,11 +63,14 @@ import com.darkwisp.app.repo.Nip05Repository
 import com.darkwisp.app.repo.RelayInfoRepository
 import com.darkwisp.app.repo.TranslationRepository
 import com.darkwisp.app.ui.component.NoteActions
+import com.darkwisp.app.ui.component.CollapsedRepliesRow
 import com.darkwisp.app.ui.component.GalleryCard
 import com.darkwisp.app.ui.component.isGalleryEvent
 import com.darkwisp.app.ui.component.PostCard
+import com.darkwisp.app.ui.component.threadConnector
+import com.darkwisp.app.ui.component.threadIndentDp
 import com.darkwisp.app.viewmodel.ThreadViewModel
-import kotlin.math.min
+import com.darkwisp.app.viewmodel.thread.ThreadItem
 import kotlinx.coroutines.launch
 
 @OptIn(ExperimentalMaterial3Api::class)
@@ -131,6 +129,14 @@ fun ThreadScreen(
     var showRootButton by remember { mutableStateOf(false) }
     var previousIndex by remember { mutableIntStateOf(0) }
     var previousOffset by remember { mutableIntStateOf(0) }
+    // When expanding a folded branch, hold the viewport steady on the note above the button:
+    // capture the top visible item + its scroll offset, then snap back to it once the subtree is
+    // inserted so the screen keeps its exact position.
+    var restoreAnchor by remember { mutableStateOf<Pair<Any, Int>?>(null) }
+
+    // The sticky reply bar targets whichever note is centered in the viewport, not always the root.
+    var focusedReplyEvent by remember { mutableStateOf<NostrEvent?>(null) }
+    val threadState = rememberUpdatedState(flatThread)
 
     LaunchedEffect(listState.isScrollInProgress) {
         if (listState.isScrollInProgress) {
@@ -164,6 +170,21 @@ fun ThreadScreen(
         }
     }
 
+    // After an inline expand inserts a subtree, restore the captured viewport position so the
+    // note above the button stays exactly where it was.
+    LaunchedEffect(restoreAnchor, flatThread) {
+        val (anchorKey, anchorOffset) = restoreAnchor ?: return@LaunchedEffect
+        val index = flatThread.indexOfFirst { it.key == anchorKey }
+        if (index >= 0) listState.scrollToItem(index, anchorOffset)
+        restoreAnchor = null
+    }
+
+    LaunchedEffect(listState) {
+        snapshotFlow { listState.firstVisibleItemIndex }.collect { idx ->
+            focusedReplyEvent = (threadState.value.getOrNull(idx) as? ThreadItem.Post)?.event
+        }
+    }
+
     val reactionVersion by eventRepo.reactionVersion.collectAsState()
     val zapVersion by eventRepo.zapVersion.collectAsState()
     val replyCountVersion by eventRepo.replyCountVersion.collectAsState()
@@ -217,7 +238,14 @@ fun ThreadScreen(
         Toast.makeText(zapDisabledContext, zapDisabledMessage, Toast.LENGTH_SHORT).show()
     }
 
-    val focalEvent = flatThread.firstOrNull()?.first
+    val expandBranch: (String) -> Unit = { anchorId ->
+        listState.layoutInfo.visibleItemsInfo.firstOrNull()?.let { first ->
+            restoreAnchor = first.key to listState.firstVisibleItemScrollOffset
+        }
+        viewModel.expandBranch(anchorId)
+    }
+
+    val focalEvent = (flatThread.firstOrNull() as? ThreadItem.Post)?.event
     Scaffold(
         contentWindowInsets = WindowInsets(0, 0, 0, 0),
         topBar = {
@@ -234,9 +262,10 @@ fun ThreadScreen(
             )
         },
         bottomBar = {
+            val replyTarget = focusedReplyEvent ?: focalEvent
             ThreadReplyBar(
-                enabled = focalEvent != null,
-                onClick = { focalEvent?.let { onReply(it) } }
+                enabled = replyTarget != null,
+                onClick = { replyTarget?.let { onReply(it) } }
             )
         }
     ) { padding ->
@@ -255,187 +284,178 @@ fun ThreadScreen(
                     state = listState,
                     modifier = Modifier.fillMaxSize()
                 ) {
-                    items(items = flatThread, key = { it.first.id }, contentType = { "post" }) { (event, depth) ->
-                        val profileData = eventRepo.getProfileData(event.pubkey)
-                        val likeCount = reactionVersion.let { eventRepo.getReactionCount(event.id) }
-                        val replyCount = replyCountVersion.let { eventRepo.getReplyCount(event.id) }
-                        val zapSats = zapVersion.let { eventRepo.getZapSats(event.id) }
-                        val userEmojis = reactionVersion.let { userPubkey?.let { eventRepo.getUserReactionEmojis(event.id, it) } ?: emptySet() }
-                        val reactionDetails = reactionVersion.let { eventRepo.getReactionDetails(event.id) }
-                        val zapDetailsList = zapVersion.let { eventRepo.getZapDetails(event.id) }
-                        val repostCount = repostVersion.let { eventRepo.getRepostCount(event.id) }
-                        val repostPubkeys = repostVersion.let { eventRepo.getReposterPubkeys(event.id) }
-                        val hasUserReposted = repostVersion.let { eventRepo.hasUserReposted(event.id) }
-                        val hasUserZapped = zapVersion.let { eventRepo.hasUserZapped(event.id) }
-                        val eventReactionEmojiUrls = reactionVersion.let { eventRepo.getReactionEmojiUrls(event.id) }
-                        val relayIcons = remember(relaySourceVersion, event.id) {
-                            eventRepo.getEventRelays(event.id).map { url ->
-                                url to relayInfoRepo?.getIconUrl(url)
+                    items(items = flatThread, key = { it.key }, contentType = { it.contentType }) { item ->
+                        if (item !is ThreadItem.Post) {
+                            // Folded subtree — expand inline, anchoring the note above the button.
+                            if (item is ThreadItem.CollapsedReplies) {
+                                CollapsedRepliesRow(
+                                    item = item,
+                                    onExpand = { expandBranch(item.anchor.id) },
+                                    modifier = Modifier.animateItem()
+                                )
                             }
-                        }
-                        val translationState = remember(translationVersion, event.id) {
-                            translationRepo?.getState(event.id) ?: com.darkwisp.app.repo.TranslationState()
-                        }
-                        val pollVoteCounts = remember(pollVoteVersion, event.id) {
-                            if (event.kind == 1068) eventRepo.getPollVoteCounts(event.id) else emptyMap()
-                        }
-                        val pollTotalVotes = remember(pollVoteVersion, event.id) {
-                            if (event.kind == 1068) eventRepo.getPollTotalVotes(event.id) else 0
-                        }
-                        val userPollVotes = remember(pollVoteVersion, event.id) {
-                            if (event.kind == 1068) eventRepo.getUserPollVotes(event.id) else emptyList()
-                        }
-                        val zapPollSatsCounts = remember(pollVoteVersion, event.id) {
-                            if (event.kind == 6969) eventRepo.getZapPollSatsCounts(event.id) else emptyMap()
-                        }
-                        val zapPollTotalSats = remember(pollVoteVersion, event.id) {
-                            if (event.kind == 6969) eventRepo.getZapPollTotalSats(event.id) else 0L
-                        }
-                        val userZapPollVote = remember(pollVoteVersion, event.id) {
-                            if (event.kind == 6969) eventRepo.getUserZapPollVote(event.id) else null
-                        }
-                        val indentStepDp = 12.dp
-                        val clampedDepth = min(depth, 5)
-                        val cornerRadiusDp = 8.dp
-                        val lineColor = MaterialTheme.colorScheme.outlineVariant.copy(alpha = 0.5f)
-                        val showConnector = depth > 0
-                        Box(
-                            modifier = Modifier
-                                .fillMaxWidth()
-                                .drawBehind {
-                                    if (!showConnector) return@drawBehind
-                                    val lineX = (clampedDepth * indentStepDp.toPx()) - 8.dp.toPx() + 1.dp.toPx()
-                                    val r = cornerRadiusDp.toPx()
-                                    val strokePx = 1.dp.toPx()
-                                    drawLine(
-                                        color = lineColor,
-                                        start = Offset(lineX, 0f),
-                                        end = Offset(lineX, size.height - r),
-                                        strokeWidth = strokePx
+                        } else {
+                            val event = item.event
+                            val depth = item.depth
+                            val profileData = eventRepo.getProfileData(event.pubkey)
+                            val likeCount = reactionVersion.let { eventRepo.getReactionCount(event.id) }
+                            val replyCount = replyCountVersion.let { eventRepo.getReplyCount(event.id) }
+                            val zapSats = zapVersion.let { eventRepo.getZapSats(event.id) }
+                            val userEmojis = reactionVersion.let { userPubkey?.let { eventRepo.getUserReactionEmojis(event.id, it) } ?: emptySet() }
+                            val reactionDetails = reactionVersion.let { eventRepo.getReactionDetails(event.id) }
+                            val zapDetailsList = zapVersion.let { eventRepo.getZapDetails(event.id) }
+                            val repostCount = repostVersion.let { eventRepo.getRepostCount(event.id) }
+                            val repostPubkeys = repostVersion.let { eventRepo.getReposterPubkeys(event.id) }
+                            val hasUserReposted = repostVersion.let { eventRepo.hasUserReposted(event.id) }
+                            val hasUserZapped = zapVersion.let { eventRepo.hasUserZapped(event.id) }
+                            val eventReactionEmojiUrls = reactionVersion.let { eventRepo.getReactionEmojiUrls(event.id) }
+                            val relayIcons = remember(relaySourceVersion, event.id) {
+                                eventRepo.getEventRelays(event.id).map { url ->
+                                    url to relayInfoRepo?.getIconUrl(url)
+                                }
+                            }
+                            val translationState = remember(translationVersion, event.id) {
+                                translationRepo?.getState(event.id) ?: com.darkwisp.app.repo.TranslationState()
+                            }
+                            val pollVoteCounts = remember(pollVoteVersion, event.id) {
+                                if (event.kind == 1068) eventRepo.getPollVoteCounts(event.id) else emptyMap()
+                            }
+                            val pollTotalVotes = remember(pollVoteVersion, event.id) {
+                                if (event.kind == 1068) eventRepo.getPollTotalVotes(event.id) else 0
+                            }
+                            val userPollVotes = remember(pollVoteVersion, event.id) {
+                                if (event.kind == 1068) eventRepo.getUserPollVotes(event.id) else emptyList()
+                            }
+                            val zapPollSatsCounts = remember(pollVoteVersion, event.id) {
+                                if (event.kind == 6969) eventRepo.getZapPollSatsCounts(event.id) else emptyMap()
+                            }
+                            val zapPollTotalSats = remember(pollVoteVersion, event.id) {
+                                if (event.kind == 6969) eventRepo.getZapPollTotalSats(event.id) else 0L
+                            }
+                            val userZapPollVote = remember(pollVoteVersion, event.id) {
+                                if (event.kind == 6969) eventRepo.getUserZapPollVote(event.id) else null
+                            }
+                            val indentPadding = threadIndentDp(depth)
+                            val lineColor = MaterialTheme.colorScheme.outlineVariant.copy(alpha = 0.5f)
+                            val showConnector = depth > 0
+                            Box(
+                                modifier = Modifier
+                                    .animateItem()
+                                    .fillMaxWidth()
+                                    .threadConnector(
+                                        show = showConnector,
+                                        indent = indentPadding,
+                                        lineColor = lineColor,
+                                        dashedTop = item.connectorStartsMidAir
                                     )
-                                    drawArc(
-                                        color = lineColor,
-                                        startAngle = 90f,
-                                        sweepAngle = 90f,
-                                        useCenter = false,
-                                        topLeft = Offset(lineX, size.height - 2f * r),
-                                        size = Size(2f * r, 2f * r),
-                                        style = Stroke(width = strokePx, cap = StrokeCap.Round)
+                            ) {
+                                if (isGalleryEvent(event)) {
+                                    GalleryCard(
+                                        event = event,
+                                        profile = profileData,
+                                        onReply = { onReply(event) },
+                                        onProfileClick = { onProfileClick(event.pubkey) },
+                                        onNavigateToProfile = onProfileClick,
+                                        onNoteClick = { onNoteClick(event) },
+                                        onReact = { emoji -> onReact(event, emoji) },
+                                        userReactionEmojis = userEmojis,
+                                        onRepost = { onRepost(event) },
+                                        onQuote = { onQuote(event) },
+                                        hasUserReposted = hasUserReposted,
+                                        repostCount = repostCount,
+                                        onZap = { onZap(event) },
+                                        hasUserZapped = hasUserZapped,
+                                        likeCount = likeCount,
+                                        replyCount = replyCount,
+                                        zapSats = zapSats,
+                                        isZapAnimating = event.id in zapAnimatingIds,
+                                        isZapInProgress = event.id in zapInProgressIds,
+                                        eventRepo = eventRepo,
+                                        reactionDetails = reactionDetails,
+                                        zapDetails = zapDetailsList,
+                                        repostDetails = repostPubkeys,
+                                        reactionEmojiUrls = eventReactionEmojiUrls,
+                                        resolvedEmojis = resolvedEmojis,
+                                        unicodeEmojis = unicodeEmojis,
+                                        onOpenEmojiLibrary = onOpenEmojiLibrary,
+                                        relayIcons = relayIcons,
+                                        onNavigateToProfileFromDetails = onProfileClick,
+                                        onFollowAuthor = { onToggleFollow(event.pubkey) },
+                                        onBlockAuthor = { onBlockUser(event.pubkey) },
+                                        isFollowingAuthor = followList.let { contactRepo.isFollowing(event.pubkey) },
+                                        isOwnEvent = event.pubkey == userPubkey,
+                                        onAddToList = { onAddToList(event.id) },
+                                        isInList = event.id in listedIds,
+                                        onPin = { onTogglePin(event.id) },
+                                        isPinned = event.id in pinnedIds,
+                                        onDelete = { onDeleteEvent(event.id, event.kind) },
+                                        nip05Repo = nip05Repo,
+                                        onQuotedNoteClick = onQuotedNoteClick,
+                                        noteActions = noteActions,
+                                        showDivider = !showConnector,
+                                        modifier = Modifier.padding(start = indentPadding)
                                     )
-                                    drawLine(
-                                        color = lineColor,
-                                        start = Offset(lineX + r, size.height),
-                                        end = Offset(size.width, size.height),
-                                        strokeWidth = strokePx
+                                } else {
+                                    PostCard(
+                                        event = event,
+                                        profile = profileData,
+                                        onReply = { onReply(event) },
+                                        onProfileClick = { onProfileClick(event.pubkey) },
+                                        onNavigateToProfile = onProfileClick,
+                                        onNoteClick = { onNoteClick(event) },
+                                        onReact = { emoji -> onReact(event, emoji) },
+                                        userReactionEmojis = userEmojis,
+                                        onRepost = { onRepost(event) },
+                                        onQuote = { onQuote(event) },
+                                        hasUserReposted = hasUserReposted,
+                                        repostCount = repostCount,
+                                        onZap = { onZap(event) },
+                                        onZapLongPress = { onZapInstant(event) },
+                                        hasUserZapped = hasUserZapped,
+                                        likeCount = likeCount,
+                                        replyCount = replyCount,
+                                        zapSats = zapSats,
+                                        isZapAnimating = event.id in zapAnimatingIds,
+                                        isZapInProgress = event.id in zapInProgressIds,
+                                        eventRepo = eventRepo,
+                                        reactionDetails = reactionDetails,
+                                        zapDetails = zapDetailsList,
+                                        repostDetails = repostPubkeys,
+                                        reactionEmojiUrls = eventReactionEmojiUrls,
+                                        resolvedEmojis = resolvedEmojis,
+                                        unicodeEmojis = unicodeEmojis,
+                                        onOpenEmojiLibrary = onOpenEmojiLibrary,
+                                        relayIcons = relayIcons,
+                                        onNavigateToProfileFromDetails = onProfileClick,
+                                        onFollowAuthor = { onToggleFollow(event.pubkey) },
+                                        onBlockAuthor = { onBlockUser(event.pubkey) },
+                                        isFollowingAuthor = followList.let { contactRepo.isFollowing(event.pubkey) },
+                                        isOwnEvent = event.pubkey == userPubkey,
+                                        isPrivate = eventRepo.isPrivate(event.id),
+                                        zapEnabled = !eventRepo.isPrivate(event.id) || canPrivateZapFor(event),
+                                        onZapDisabledTap = onZapDisabledTap,
+                                        onAddToList = { onAddToList(event.id) },
+                                        isInList = event.id in listedIds,
+                                        onPin = { onTogglePin(event.id) },
+                                        isPinned = event.id in pinnedIds,
+                                        onDelete = { onDeleteEvent(event.id, event.kind) },
+                                        nip05Repo = nip05Repo,
+                                        onQuotedNoteClick = onQuotedNoteClick,
+                                        noteActions = noteActions,
+                                        translationState = translationState,
+                                        onTranslate = { translationRepo?.translate(event.id, event.content) },
+                                        pollVoteCounts = pollVoteCounts,
+                                        pollTotalVotes = pollTotalVotes,
+                                        userPollVotes = userPollVotes,
+                                        onPollVote = { optionIds -> onPollVote(event.id, optionIds) },
+                                        zapPollSatsCounts = zapPollSatsCounts,
+                                        zapPollTotalSats = zapPollTotalSats,
+                                        userZapPollVote = userZapPollVote,
+                                        onZapPollVote = { idx -> onZapPollVote(event.id, idx) },
+                                        showDivider = !showConnector,
+                                        modifier = Modifier.padding(start = indentPadding)
                                     )
                                 }
-                        ) {
-                            if (isGalleryEvent(event)) {
-                                GalleryCard(
-                                    event = event,
-                                    profile = profileData,
-                                    onReply = { onReply(event) },
-                                    onProfileClick = { onProfileClick(event.pubkey) },
-                                    onNavigateToProfile = onProfileClick,
-                                    onNoteClick = { onNoteClick(event) },
-                                    onReact = { emoji -> onReact(event, emoji) },
-                                    userReactionEmojis = userEmojis,
-                                    onRepost = { onRepost(event) },
-                                    onQuote = { onQuote(event) },
-                                    hasUserReposted = hasUserReposted,
-                                    repostCount = repostCount,
-                                    onZap = { onZap(event) },
-                                    hasUserZapped = hasUserZapped,
-                                    likeCount = likeCount,
-                                    replyCount = replyCount,
-                                    zapSats = zapSats,
-                                    isZapAnimating = event.id in zapAnimatingIds,
-                                    isZapInProgress = event.id in zapInProgressIds,
-                                    eventRepo = eventRepo,
-                                    reactionDetails = reactionDetails,
-                                    zapDetails = zapDetailsList,
-                                    repostDetails = repostPubkeys,
-                                    reactionEmojiUrls = eventReactionEmojiUrls,
-                                    resolvedEmojis = resolvedEmojis,
-                                    unicodeEmojis = unicodeEmojis,
-                                    onOpenEmojiLibrary = onOpenEmojiLibrary,
-                                    relayIcons = relayIcons,
-                                    onNavigateToProfileFromDetails = onProfileClick,
-                                    onFollowAuthor = { onToggleFollow(event.pubkey) },
-                                    onBlockAuthor = { onBlockUser(event.pubkey) },
-                                    isFollowingAuthor = followList.let { contactRepo.isFollowing(event.pubkey) },
-                                    isOwnEvent = event.pubkey == userPubkey,
-                                    onAddToList = { onAddToList(event.id) },
-                                    isInList = event.id in listedIds,
-                                    onPin = { onTogglePin(event.id) },
-                                    isPinned = event.id in pinnedIds,
-                                    onDelete = { onDeleteEvent(event.id, event.kind) },
-                                    nip05Repo = nip05Repo,
-                                    onQuotedNoteClick = onQuotedNoteClick,
-                                    noteActions = noteActions,
-                                    showDivider = !showConnector,
-                                    modifier = Modifier.padding(start = (clampedDepth * indentStepDp.value).dp)
-                                )
-                            } else {
-                                PostCard(
-                                    event = event,
-                                    profile = profileData,
-                                    onReply = { onReply(event) },
-                                    onProfileClick = { onProfileClick(event.pubkey) },
-                                    onNavigateToProfile = onProfileClick,
-                                    onNoteClick = { onNoteClick(event) },
-                                    onReact = { emoji -> onReact(event, emoji) },
-                                    userReactionEmojis = userEmojis,
-                                    onRepost = { onRepost(event) },
-                                    onQuote = { onQuote(event) },
-                                    hasUserReposted = hasUserReposted,
-                                    repostCount = repostCount,
-                                    onZap = { onZap(event) },
-                                    onZapLongPress = { onZapInstant(event) },
-                                    hasUserZapped = hasUserZapped,
-                                    likeCount = likeCount,
-                                    replyCount = replyCount,
-                                    zapSats = zapSats,
-                                    isZapAnimating = event.id in zapAnimatingIds,
-                                    isZapInProgress = event.id in zapInProgressIds,
-                                    eventRepo = eventRepo,
-                                    reactionDetails = reactionDetails,
-                                    zapDetails = zapDetailsList,
-                                    repostDetails = repostPubkeys,
-                                    reactionEmojiUrls = eventReactionEmojiUrls,
-                                    resolvedEmojis = resolvedEmojis,
-                                    unicodeEmojis = unicodeEmojis,
-                                    onOpenEmojiLibrary = onOpenEmojiLibrary,
-                                    relayIcons = relayIcons,
-                                    onNavigateToProfileFromDetails = onProfileClick,
-                                    onFollowAuthor = { onToggleFollow(event.pubkey) },
-                                    onBlockAuthor = { onBlockUser(event.pubkey) },
-                                    isFollowingAuthor = followList.let { contactRepo.isFollowing(event.pubkey) },
-                                    isOwnEvent = event.pubkey == userPubkey,
-                                    isPrivate = eventRepo.isPrivate(event.id),
-                                    zapEnabled = !eventRepo.isPrivate(event.id) || canPrivateZapFor(event),
-                                    onZapDisabledTap = onZapDisabledTap,
-                                    onAddToList = { onAddToList(event.id) },
-                                    isInList = event.id in listedIds,
-                                    onPin = { onTogglePin(event.id) },
-                                    isPinned = event.id in pinnedIds,
-                                    onDelete = { onDeleteEvent(event.id, event.kind) },
-                                    nip05Repo = nip05Repo,
-                                    onQuotedNoteClick = onQuotedNoteClick,
-                                    noteActions = noteActions,
-                                    translationState = translationState,
-                                    onTranslate = { translationRepo?.translate(event.id, event.content) },
-                                    pollVoteCounts = pollVoteCounts,
-                                    pollTotalVotes = pollTotalVotes,
-                                    userPollVotes = userPollVotes,
-                                    onPollVote = { optionIds -> onPollVote(event.id, optionIds) },
-                                    zapPollSatsCounts = zapPollSatsCounts,
-                                    zapPollTotalSats = zapPollTotalSats,
-                                    userZapPollVote = userZapPollVote,
-                                    onZapPollVote = { idx -> onZapPollVote(event.id, idx) },
-                                    showDivider = !showConnector,
-                                    modifier = Modifier.padding(start = (clampedDepth * indentStepDp.value).dp)
-                                )
                             }
                         }
                     }

app/src/main/kotlin/com/darkwisp/app/viewmodel/ArticleViewModel.kt

@@ -15,6 +15,8 @@ import com.darkwisp.app.repo.EventRepository
 import com.darkwisp.app.repo.MetadataFetcher
 import com.darkwisp.app.repo.RelayHintStore
 import com.darkwisp.app.repo.RelayListRepository
+import com.darkwisp.app.viewmodel.thread.ThreadFlattener
+import com.darkwisp.app.viewmodel.thread.ThreadItem
 import kotlinx.coroutines.Job
 import kotlinx.coroutines.delay
 import kotlinx.coroutines.flow.MutableStateFlow
@@ -45,13 +47,16 @@ class ArticleViewModel : ViewModel() {
     val definedKinds: StateFlow<List<CustomNip.DefinedKind>> = _definedKinds
 
     // Comments
-    private val _comments = MutableStateFlow<List<Pair<NostrEvent, Int>>>(emptyList())
-    val comments: StateFlow<List<Pair<NostrEvent, Int>>> = _comments
+    private val _comments = MutableStateFlow<List<ThreadItem>>(emptyList())
+    val comments: StateFlow<List<ThreadItem>> = _comments
 
     private val _isCommentsLoading = MutableStateFlow(false)
     val isCommentsLoading: StateFlow<Boolean> = _isCommentsLoading
 
     private val commentEvents = mutableMapOf<String, NostrEvent>()
+    private var currentArticleEventId: String? = null
+    /** Anchors whose folded comment subtree the user expanded inline. */
+    private val expandedIds = mutableSetOf<String>()
     private var collectorJob: Job? = null
     private var engagementCollectorJob: Job? = null
     private var rebuildJob: Job? = null
@@ -111,6 +116,7 @@ class ArticleViewModel : ViewModel() {
         this.topRelayUrls = topRelayUrls
         this.relayListRepoRef = relayListRepo
         this.relayHintStoreRef = relayHintStore
+        this.currentArticleEventId = articleEventId
         _isCommentsLoading.value = true
 
         val coordinate = "$kind:$author:$dTag"
@@ -335,34 +341,25 @@ class ArticleViewModel : ViewModel() {
             children.sortBy { it.created_at }
         }
 
-        val result = mutableListOf<Pair<NostrEvent, Int>>()
-        val visited = mutableSetOf<String>()
-
-        val rootChildren = parentToChildren["root"] ?: emptyList()
-        for (child in rootChildren) {
-            if (child.id in visited) continue
-            visited.add(child.id)
-            result.add(child to 0)
-            dfs(child.id, 1, parentToChildren, result, visited)
-        }
-
-        _comments.value = result
+        // Article comments share note threads' progressive disclosure: deeper-than-cap
+        // subtrees fold behind an inline "Show N more replies" affordance (expandBranch).
+        _comments.value = ThreadFlattener.flatten(
+            rootId = "root",
+            rootEvent = null,
+            parentToChildren = parentToChildren,
+            expandedIds = expandedIds,
+            // Fan-out ("show more replies") cap stays disabled for article comments.
+            maxSiblingsInline = Int.MAX_VALUE
+        )
     }
 
-    private fun dfs(
-        parentId: String,
-        depth: Int,
-        parentToChildren: Map<String, List<NostrEvent>>,
-        result: MutableList<Pair<NostrEvent, Int>>,
-        visited: MutableSet<String>
-    ) {
-        val children = parentToChildren[parentId] ?: return
-        for (child in children) {
-            if (child.id in visited) continue
-            visited.add(child.id)
-            result.add(child to depth)
-            dfs(child.id, depth + 1, parentToChildren, result, visited)
-        }
+    /** Expand a folded comment subtree inline. */
+    fun expandBranch(anchorId: String) {
+        if (expandedIds.add(anchorId)) rebuildTree(currentArticleEventId)
+    }
+
+    fun collapseBranch(anchorId: String) {
+        if (expandedIds.remove(anchorId)) rebuildTree(currentArticleEventId)
     }
 
     private fun parseAndEmit(event: NostrEvent) {

app/src/main/kotlin/com/darkwisp/app/viewmodel/ThreadViewModel.kt

@@ -20,6 +20,8 @@ import com.darkwisp.app.repo.RelayHintStore
 import com.darkwisp.app.repo.RelayListRepository
 import com.darkwisp.app.repo.SafetyPreferences
 import com.darkwisp.app.repo.SpamAuthorCache
+import com.darkwisp.app.viewmodel.thread.ThreadFlattener
+import com.darkwisp.app.viewmodel.thread.ThreadItem
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.Job
 import kotlinx.coroutines.delay
@@ -32,8 +34,8 @@ class ThreadViewModel : ViewModel() {
     private val _rootEvent = MutableStateFlow<NostrEvent?>(null)
     val rootEvent: StateFlow<NostrEvent?> = _rootEvent
 
-    private val _flatThread = MutableStateFlow<List<Pair<NostrEvent, Int>>>(emptyList())
-    val flatThread: StateFlow<List<Pair<NostrEvent, Int>>> = _flatThread
+    private val _flatThread = MutableStateFlow<List<ThreadItem>>(emptyList())
+    val flatThread: StateFlow<List<ThreadItem>> = _flatThread
 
     private val _isLoading = MutableStateFlow(true)
     val isLoading: StateFlow<Boolean> = _isLoading
@@ -50,6 +52,8 @@ class ThreadViewModel : ViewModel() {
     private val threadEvents = mutableMapOf<String, NostrEvent>()
     private var rootId: String = ""
     private var scrollTargetId: String? = null
+    /** Anchors whose depth-capped subtree the user expanded inline. */
+    private val expandedIds = mutableSetOf<String>()
     private var muteRepo: MuteRepository? = null
     private val activeMetadataSubs = mutableListOf<String>()
     private var relayPoolRef: RelayPool? = null
@@ -93,6 +97,15 @@ class ThreadViewModel : ViewModel() {
         scheduleRebuild()
     }
 
+    /** Expand a folded subtree inline. Scroll-position anchoring is handled in the screen. */
+    fun expandBranch(anchorId: String) {
+        if (expandedIds.add(anchorId)) rebuildTree()
+    }
+
+    fun collapseBranch(anchorId: String) {
+        if (expandedIds.remove(anchorId)) rebuildTree()
+    }
+
     fun loadThread(
         eventId: String,
         eventRepo: EventRepository,
@@ -467,53 +480,27 @@ class ThreadViewModel : ViewModel() {
         }
 
         for (children in parentToChildren.values) {
-            children.sortWith(Comparator { a, b ->
-                a.created_at.compareTo(b.created_at)
-            })
+            children.sortBy { it.created_at }
         }
 
-        val result = mutableListOf<Pair<NostrEvent, Int>>()
-        val visited = mutableSetOf<String>()
         val root = threadEvents[rootId]
-        if (root != null) {
-            result.add(root to 0)
-            visited.add(root.id)
-            dfs(rootId, 1, parentToChildren, result, visited)
-        } else {
-            // Root not yet loaded — render replies we have
-            val rootChildren = parentToChildren[rootId] ?: emptyList()
-            for (child in rootChildren) {
-                if (child.id in visited) continue
-                visited.add(child.id)
-                result.add(child to 0)
-                dfs(child.id, 1, parentToChildren, result, visited)
-            }
-        }
-
-        _flatThread.value = result
+        val flattened = ThreadFlattener.flatten(
+            rootId = rootId,
+            rootEvent = root,
+            parentToChildren = parentToChildren,
+            expandedIds = expandedIds,
+            scrollTargetId = scrollTargetId,
+            // Fan-out ("show more replies") cap lands with its UI toggle in a follow-up.
+            maxSiblingsInline = Int.MAX_VALUE
+        )
+        _flatThread.value = flattened
 
         val targetId = scrollTargetId
         if (targetId != null) {
-            val index = result.indexOfFirst { it.first.id == targetId }
+            val index = flattened.indexOfFirst { it is ThreadItem.Post && it.event.id == targetId }
             if (index >= 0) {
                 _scrollToIndex.value = index
             }
         }
     }
-
-    private fun dfs(
-        parentId: String,
-        depth: Int,
-        parentToChildren: Map<String, List<NostrEvent>>,
-        result: MutableList<Pair<NostrEvent, Int>>,
-        visited: MutableSet<String>
-    ) {
-        val children = parentToChildren[parentId] ?: return
-        for (child in children) {
-            if (child.id in visited) continue
-            visited.add(child.id)
-            result.add(child to depth)
-            dfs(child.id, depth + 1, parentToChildren, result, visited)
-        }
-    }
 }

app/src/main/kotlin/com/darkwisp/app/viewmodel/thread/ThreadFlattener.kt

@@ -0,0 +1,202 @@
+package com.darkwisp.app.viewmodel.thread
+
+import com.darkwisp.app.nostr.NostrEvent
+
+/**
+ * Pure, side-effect-free flattener that turns a parent→children reply tree into a
+ * [ThreadItem] list for the UI. Shared by [com.darkwisp.app.viewmodel.ThreadViewModel] and
+ * [com.darkwisp.app.viewmodel.ArticleViewModel] so the two paths can't drift.
+ *
+ * Progressive disclosure (so long/deep threads stay legible — "who is replying to whom"):
+ *  - **Depth cap**: replies deeper than [DEPTH_CAP] levels fold behind a [ThreadItem.CollapsedReplies]
+ *    affordance that the user expands *inline* (scroll position preserved) rather than
+ *    navigating away. Putting the anchor in [expandedIds] overrides the cap for that branch.
+ *  - **Collapsible branches**: a node in [collapsedIds] emits only itself; its descendants fold
+ *    into the "+N replies" affordance the UI renders from [ThreadItem.Post.descendantCount].
+ *  - **High fan-out**: a parent with more than [maxSiblingsInline] direct replies shows the first
+ *    few then a [ThreadItem.ShowMoreReplies] affordance (unless it is in [expandedFanOut]).
+ *
+ * The [scrollTargetId] path (the note to scroll to, plus all its ancestors) is exempt from
+ * collapse and the depth cap, so a freshly-published reply is always reachable/visible.
+ *
+ * All inputs are assumed already cleaned (deletions/blocked/spam filtered) and chronologically
+ * sorted within each sibling group — done by the caller's `rebuildTree`.
+ */
+object ThreadFlattener {
+    /** Root is depth 0; replies at depths 1..DEPTH_CAP render as posts; deeper replies fold. */
+    const val DEPTH_CAP = 3
+
+    /** Default direct-replies shown inline before a "show more" affordance appears under a parent. */
+    const val MAX_SIBLINGS_INLINE = 4
+
+    fun flatten(
+        rootId: String,
+        rootEvent: NostrEvent?,
+        parentToChildren: Map<String, List<NostrEvent>>,
+        collapsedIds: Set<String> = emptySet(),
+        expandedIds: Set<String> = emptySet(),
+        expandedFanOut: Set<String> = emptySet(),
+        scrollTargetId: String? = null,
+        maxSiblingsInline: Int = MAX_SIBLINGS_INLINE,
+        depthCap: Int = DEPTH_CAP
+    ): List<ThreadItem> {
+        val subtreeSizes = computeSubtreeSizes(parentToChildren)
+        val pathToTarget = scrollTargetId?.let { ancestorsOf(it, parentToChildren) } ?: emptySet()
+        val raw = mutableListOf<ThreadItem>()
+        val visited = HashSet<String>()
+
+        if (rootEvent != null) {
+            visited.add(rootEvent.id)
+            raw.add(
+                ThreadItem.Post(
+                    event = rootEvent,
+                    depth = 0,
+                    descendantCount = subtreeSizes[rootEvent.id] ?: 0,
+                    collapsed = false
+                )
+            )
+            walk(rootEvent, 0, parentToChildren, subtreeSizes, collapsedIds, expandedIds, expandedFanOut, pathToTarget, visited, raw, maxSiblingsInline, depthCap, false)
+        } else {
+            // Root not yet loaded — render the top-level replies we have, each as a depth-0 root.
+            for (child in parentToChildren[rootId].orEmpty()) {
+                if (child.id in visited) continue
+                visited.add(child.id)
+                val collapsed = child.id in collapsedIds && child.id !in pathToTarget
+                raw.add(
+                    ThreadItem.Post(
+                        event = child,
+                        depth = 0,
+                        descendantCount = subtreeSizes[child.id] ?: 0,
+                        collapsed = collapsed
+                    )
+                )
+                walk(child, 0, parentToChildren, subtreeSizes, collapsedIds, expandedIds, expandedFanOut, pathToTarget, visited, raw, maxSiblingsInline, depthCap, false)
+            }
+        }
+        return applyConnectorFlags(raw)
+    }
+
+    private fun walk(
+        parentEvent: NostrEvent,
+        parentDepth: Int,
+        parentToChildren: Map<String, List<NostrEvent>>,
+        subtreeSizes: Map<String, Int>,
+        collapsedIds: Set<String>,
+        expandedIds: Set<String>,
+        expandedFanOut: Set<String>,
+        pathToTarget: Set<String>,
+        visited: HashSet<String>,
+        result: MutableList<ThreadItem>,
+        maxSiblingsInline: Int,
+        depthCap: Int,
+        insideExpanded: Boolean
+    ) {
+        val children = parentToChildren[parentEvent.id] ?: return
+        val childDepth = parentDepth + 1
+        val fanOut = children.size > maxSiblingsInline && parentEvent.id !in expandedFanOut
+        val visibleChildren = if (fanOut) children.take(maxSiblingsInline) else children
+
+        for (child in visibleChildren) {
+            if (child.id in visited) continue
+            visited.add(child.id)
+            val collapsed = child.id in collapsedIds && child.id !in pathToTarget
+            val hasChildren = !parentToChildren[child.id].isNullOrEmpty()
+            result.add(
+                ThreadItem.Post(
+                    event = child,
+                    depth = childDepth,
+                    descendantCount = subtreeSizes[child.id] ?: 0,
+                    collapsed = collapsed
+                )
+            )
+            // Fold the subtree when capped (unless the user expanded this branch, or it's on the
+            // scroll-to-reply path). Expanded branches descend normally and the cap reapplies
+            // one level deeper, so expansion is progressive.
+            val capHere = childDepth >= depthCap &&
+                child.id !in pathToTarget &&
+                child.id !in expandedIds &&
+                !insideExpanded &&
+                hasChildren
+            when {
+                collapsed || (capHere && !hasChildren) -> {
+                    // Descendants hidden — the "+N replies" affordance renders on the Post row.
+                }
+                capHere -> {
+                    result.add(
+                        ThreadItem.CollapsedReplies(
+                            anchor = child,
+                            depth = childDepth + 1,
+                            hiddenCount = subtreeSizes[child.id] ?: 0
+                        )
+                    )
+                }
+                else -> walk(child, childDepth, parentToChildren, subtreeSizes, collapsedIds, expandedIds, expandedFanOut, pathToTarget, visited, result, maxSiblingsInline, depthCap, insideExpanded || child.id in expandedIds)
+            }
+        }
+
+        if (fanOut) {
+            result.add(
+                ThreadItem.ShowMoreReplies(
+                    parent = parentEvent,
+                    depth = childDepth,
+                    hiddenCount = children.size - maxSiblingsInline
+                )
+            )
+        }
+    }
+
+    /**
+     * Marks each [ThreadItem.Post]'s rail as "starting in mid-air" when the row immediately above
+     * (ignoring affordance rows) is not a Post at the same depth — i.e. the depth-guide spine is
+     * broken, so the rail's top would otherwise float. The UI dashes the top of such rails to
+     * signal they continue upward to the parent.
+     */
+    private fun applyConnectorFlags(items: List<ThreadItem>): List<ThreadItem> {
+        var prevDepth = -1
+        return items.map { item ->
+            if (item is ThreadItem.Post) {
+                val midAir = item.depth > 0 && prevDepth != item.depth
+                prevDepth = item.depth
+                if (midAir == item.connectorStartsMidAir) item else item.copy(connectorStartsMidAir = midAir)
+            } else item
+        }
+    }
+
+    /** Total descendants of each node (excluding the node itself), cycle-guarded. */
+    private fun computeSubtreeSizes(parentToChildren: Map<String, List<NostrEvent>>): Map<String, Int> {
+        val sizes = HashMap<String, Int>()
+        val visiting = HashSet<String>()
+
+        fun sizeOf(id: String): Int {
+            sizes[id]?.let { return it }
+            visiting.add(id)
+            var total = 0
+            for (child in parentToChildren[id].orEmpty()) {
+                if (child.id in visiting) continue // cycle guard
+                total += 1 + sizeOf(child.id)
+            }
+            visiting.remove(id)
+            sizes[id] = total
+            return total
+        }
+        for (id in parentToChildren.keys) sizeOf(id)
+        return sizes
+    }
+
+    /** [targetId] plus all of its ancestors (up to a missing parent or a cycle). Used to keep
+     *  the scroll-to-reply path expanded through collapse/depth-cap. */
+    private fun ancestorsOf(targetId: String, parentToChildren: Map<String, List<NostrEvent>>): Set<String> {
+        val childToParent = HashMap<String, String>()
+        for ((parentId, children) in parentToChildren) {
+            for (child in children) {
+                if (child.id !in childToParent) childToParent[child.id] = parentId
+            }
+        }
+        val result = LinkedHashSet<String>()
+        var cur: String? = targetId
+        while (cur != null && result.add(cur)) {
+            cur = childToParent[cur]
+        }
+        return result
+    }
+}

app/src/main/kotlin/com/darkwisp/app/viewmodel/thread/ThreadItem.kt

@@ -0,0 +1,56 @@
+package com.darkwisp.app.viewmodel.thread
+
+import com.darkwisp.app.nostr.NostrEvent
+
+/**
+ * One row in a flattened reply thread. Replaces the old `Pair<NostrEvent, Int>` so the list
+ * can also carry synthetic progressive-disclosure rows (a folded subtree that expands inline)
+ * with stable LazyColumn keys.
+ *
+ * Each variant carries its own [depth] so the UI's indent + connector math is uniform, plus
+ * a stable [key] and a distinct [contentType] (so Compose pools synthetic rows separately
+ * from full PostCard rows).
+ */
+sealed interface ThreadItem {
+    val depth: Int
+    val key: Any
+    val contentType: String
+
+    /** A real note row.
+     *  - [descendantCount]: full subtree size under this note (used for "+N replies" affordances).
+     *  - [connectorStartsMidAir]: true when this note's depth-guide rail has no same-depth Post
+     *    immediately above it in the rendered list — i.e. the rail's top would "start in mid-air"
+     *    rather than continuing a visible spine. The UI dashes the top of the rail in that case. */
+    data class Post(
+        val event: NostrEvent,
+        override val depth: Int,
+        val descendantCount: Int,
+        val collapsed: Boolean,
+        val connectorStartsMidAir: Boolean = false
+    ) : ThreadItem {
+        override val key: Any get() = event.id
+        override val contentType: String get() = "post"
+    }
+
+    /** A folded subtree under [anchor] that the user can expand inline, keeping scroll
+     *  position anchored on the note above. [hiddenCount] is the subtree size. */
+    data class CollapsedReplies(
+        val anchor: NostrEvent,
+        override val depth: Int,
+        val hiddenCount: Int
+    ) : ThreadItem {
+        override val key: Any get() = "collapsed_${anchor.id}"
+        override val contentType: String get() = "collapsed"
+    }
+
+    /** High-fan-out cap: [hiddenCount] sibling replies under [parent] are folded away. Tapping
+     *  expands them inline. */
+    data class ShowMoreReplies(
+        val parent: NostrEvent,
+        override val depth: Int,
+        val hiddenCount: Int
+    ) : ThreadItem {
+        override val key: Any get() = "more_${parent.id}"
+        override val contentType: String get() = "more"
+    }
+}

app/src/main/res/values/strings.xml

@@ -551,6 +551,10 @@
     <string name="thread_tap_to_show">Show</string>
     <string name="thread_tap_to_hide">Hide</string>
     <string name="thread_not_spam">Not spam</string>
+    <plurals name="thread_continue">
+        <item quantity="one">Show %1$d more reply</item>
+        <item quantity="other">Show %1$d more replies</item>
+    </plurals>
 
     <string name="settings_copy_profile_json">Copy Profile JSON</string>
     <string name="settings_profile_json_copied">Profile JSON copied</string>

app/src/test/kotlin/com/darkwisp/app/viewmodel/thread/ThreadFlattenerTest.kt

@@ -0,0 +1,108 @@
+package com.darkwisp.app.viewmodel.thread
+
+import com.darkwisp.app.nostr.NostrEvent
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertFalse
+import org.junit.Assert.assertNull
+import org.junit.Assert.assertTrue
+import org.junit.Test
+
+/**
+ * Pure-logic tests for [ThreadFlattener] — the progressive-disclosure flattener that is now the
+ * heart of the thread view (depth cap, inline expand, scroll-to-reply path exemption, cycle
+ * safety, and the "starts in mid-air" connector flag). The flattener consumes an already-parsed
+ * parent→children map, so these tests build synthetic trees directly — no NIP-10 wiring needed.
+ */
+class ThreadFlattenerTest {
+
+    private fun ev(id: String) = NostrEvent(id, "pk", 0L, 1, emptyList(), "", "")
+
+    private fun tree(vararg edges: Pair<String, List<String>>): Map<String, List<NostrEvent>> {
+        val m = HashMap<String, List<NostrEvent>>()
+        for ((parent, kids) in edges) m[parent] = kids.map(::ev)
+        return m
+    }
+
+    private fun posts(items: List<ThreadItem>) = items.filterIsInstance<ThreadItem.Post>()
+    private fun collapsed(items: List<ThreadItem>) = items.filterIsInstance<ThreadItem.CollapsedReplies>()
+
+    private val deepChain = tree(
+        "R" to listOf("A"), "A" to listOf("B"), "B" to listOf("C"),
+        "C" to listOf("D"), "D" to listOf("E")
+    )
+
+    @Test
+    fun depthCap_foldsDeepSubtree_behindCollapsedAffordance() {
+        val out = ThreadFlattener.flatten("R", ev("R"), deepChain)
+        val p = posts(out)
+        assertEquals(listOf("R", "A", "B", "C"), p.map { it.event.id })
+        assertEquals(listOf(0, 1, 2, 3), p.map { it.depth })
+        val c = collapsed(out)
+        assertEquals(1, c.size)
+        assertEquals("C", c[0].anchor.id)
+        assertEquals(2, c[0].hiddenCount) // D + E folded
+        assertNull(p.firstOrNull { it.event.id == "D" || it.event.id == "E" })
+    }
+
+    @Test
+    fun expand_revealsEntireSubtree_atOnce() {
+        // Tapping "N more replies" must reveal the whole hidden subtree at once, not one level
+        // at a time. C's subtree is D -> E (hiddenCount 2); expanding C shows both D and E.
+        val out = ThreadFlattener.flatten("R", ev("R"), deepChain, expandedIds = setOf("C"))
+        val p = posts(out)
+        assertTrue(p.any { it.event.id == "D" })
+        assertTrue(p.any { it.event.id == "E" })
+        assertTrue(collapsed(out).isEmpty()) // no re-cap inside the expanded subtree
+    }
+
+    @Test
+    fun scrollTargetPath_staysVisibleThroughCap() {
+        // E is depth 5 — normally capped — but it (and its ancestors) are exempt so a freshly
+        // published reply is always reachable/visible.
+        val out = ThreadFlattener.flatten("R", ev("R"), deepChain, scrollTargetId = "E")
+        val p = posts(out)
+        assertTrue(p.any { it.event.id == "E" })
+        assertEquals(5, p.last().depth)
+        assertTrue(collapsed(out).isEmpty())
+    }
+
+    @Test
+    fun cycle_doesNotInfiniteLoop() {
+        val out = ThreadFlattener.flatten("A", ev("A"), tree("A" to listOf("B"), "B" to listOf("A")))
+        assertEquals(listOf("A", "B"), posts(out).map { it.event.id })
+    }
+
+    @Test
+    fun collapsedBranch_hidesSubtree_andFlagsThePost() {
+        val out = ThreadFlattener.flatten(
+            "R", ev("R"),
+            tree("R" to listOf("A", "B"), "A" to listOf("A1")),
+            collapsedIds = setOf("A")
+        )
+        val p = posts(out)
+        assertTrue(p.any { it.event.id == "A" && it.collapsed })
+        assertFalse(p.any { it.event.id == "A1" })
+    }
+
+    @Test
+    fun connectorFlag_dashesOrphanedTops_butNotContinuedSiblingSpines() {
+        val out = ThreadFlattener.flatten("R", ev("R"), tree("R" to listOf("A", "B")))
+        val p = posts(out)
+        val a = p.first { it.event.id == "A" }
+        val b = p.first { it.event.id == "B" }
+        assertTrue(a.connectorStartsMidAir)  // first reply: spine broken above
+        assertFalse(b.connectorStartsMidAir) // sibling immediately below: spine continues
+    }
+
+    @Test
+    fun rootNull_rendersTopLevelRepliesAsDepthZeroRoots() {
+        val out = ThreadFlattener.flatten(
+            "R", null,
+            tree("R" to listOf("A", "B"), "A" to listOf("A1"))
+        )
+        val p = posts(out)
+        assertEquals("A", p[0].event.id)
+        assertEquals(0, p[0].depth)
+        assertTrue(p.any { it.event.id == "A1" && it.depth == 1 })
+    }
+}