Manual testing fixes:

- quartz: Event.threadRootIdOrSelf() now falls back to markedReply()?.eventId
when both markedRoot() and unmarkedRoot() are absent
- amethyst: After upstream PR #2855 split the notifications feed into
notificationsFollowing and notificationsEveryone, the hiddenUsers.flow
collector still only invalidated the original notifications feed. Extends
it to invalidate all three.
- amethyst: CardFeedContentState.refreshSuspended() takes an additive-only
path when lastNotes is populated — it only adds cards for new admissions,
never removing cards for notes that no longer pass the filter. Re-muting
mid-session correctly rejected muted-thread reactions in the filter, but
the existing cards stayed in the UI as "Show Anyway" placeholders. Calls
clear() before invalidateData() on each notification feed so the refresh
hits the full-rebuild branch and removals propagate.

amethyst/src/main/java/com/vitorpamplona/amethyst/ui/screen/loggedIn/AccountFeedContentStates.kt

@@ -138,7 +138,16 @@ class AccountFeedContentStates(
             account.hiddenUsers.flow.collect {
                 dmKnown.invalidateData()
                 dmNew.invalidateData()
+                // Re-mute removes cards, not just adds them. CardFeedContentState's
+                // refreshSuspended() takes an additive-only path when lastNotes is
+                // populated, which keeps stale cards for notes that no longer pass
+                // the filter. Clear first so the refresh hits the full-rebuild branch.
+                notifications.clear()
                 notifications.invalidateData()
+                notificationsFollowing.clear()
+                notificationsFollowing.invalidateData()
+                notificationsEveryone.clear()
+                notificationsEveryone.invalidateData()
             }
         }
     }

quartz/src/commonMain/kotlin/com/vitorpamplona/quartz/nip10Notes/BaseThreadedEvent.kt

@@ -31,7 +31,14 @@ import com.vitorpamplona.quartz.nip54Wiki.WikiNoteEvent
 import com.vitorpamplona.quartz.nip72ModCommunities.definition.CommunityDefinitionEvent
 import com.vitorpamplona.quartz.utils.lastNotNullOfOrNull
 
-fun Event.threadRootIdOrSelf(): HexKey = (this as? BaseThreadedEvent)?.root()?.eventId ?: id
+fun Event.threadRootIdOrSelf(): HexKey {
+    val threaded = this as? BaseThreadedEvent ?: return id
+    threaded.root()?.eventId?.let { return it }
+    // NIP-10 legacy single-level form: when only a "reply"-marked e-tag is
+    // present (no "root" marker), the reply target IS the conversation root.
+    threaded.markedReply()?.eventId?.let { return it }
+    return id
+}
 
 @Immutable
 open class BaseThreadedEvent(

quartz/src/commonTest/kotlin/com/vitorpamplona/quartz/nip10Notes/ThreadRootIdOrSelfTest.kt

@@ -0,0 +1,75 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.quartz.nip10Notes
+
+import kotlin.test.Test
+import kotlin.test.assertEquals
+
+class ThreadRootIdOrSelfTest {
+    private val selfId = "3b1ef90115dc6f383e9588d29c86fe3ecda6ecc98415af556cd1399731a15e09"
+    private val rootId = "41ed6fdfbe827e7e87f3bfd852270b036c199b721777593d257029d742adcb46"
+    private val parentId = "54851588857363fa077fc756c1a64528f511d39476ca37e6a781bcb7aabb9e7d"
+    private val pubKey = "b62b357c1b939ae051a361d5befd409ddda06264a7588f1a986c24b1d13cc53f"
+    private val relay = "wss://relay.damus.io"
+    private val sig = "0".repeat(128)
+
+    private fun textNote(tags: Array<Array<String>>): TextNoteEvent = TextNoteEvent(selfId, pubKey, 1778593701L, tags, "", sig)
+
+    @Test fun topLevelNote_noETags_resolvesToOwnId() {
+        // A note with no e-tags is the root of its own thread.
+        val note = textNote(emptyArray())
+        assertEquals(selfId, note.threadRootIdOrSelf())
+    }
+
+    @Test fun replyWithRootMarker_resolvesToRoot() {
+        // Modern NIP-10: explicit "root" marker.
+        val note = textNote(arrayOf(arrayOf("e", rootId, relay, "root")))
+        assertEquals(rootId, note.threadRootIdOrSelf())
+    }
+
+    @Test fun replyWithBothRootAndReplyMarkers_resolvesToRoot() {
+        // Multi-level reply: "root" marker points to thread root,
+        // "reply" marker points to immediate parent.
+        val note =
+            textNote(
+                arrayOf(
+                    arrayOf("e", rootId, relay, "root"),
+                    arrayOf("e", parentId, relay, "reply"),
+                ),
+            )
+        assertEquals(rootId, note.threadRootIdOrSelf())
+    }
+
+    @Test fun replyWithOnlyReplyMarker_resolvesToReplyTarget() {
+        // NIP-10 legacy single-level form: a one-level reply marked only
+        // "reply" with no "root" marker. The "reply" target IS the
+        // conversation root. Regression case from issue #161 device QA.
+        val note = textNote(arrayOf(arrayOf("e", rootId, relay, "reply")))
+        assertEquals(rootId, note.threadRootIdOrSelf())
+    }
+
+    @Test fun replyWithUnmarkedETag_resolvesToTaggedEvent() {
+        // Positional NIP-10: e-tag with no marker. Treated as root by
+        // BaseThreadedEvent.unmarkedRoot().
+        val note = textNote(arrayOf(arrayOf("e", rootId, relay)))
+        assertEquals(rootId, note.threadRootIdOrSelf())
+    }
+}