Code review:

- consolidate thread-root resolution
- consolidate mute-state writes

amethyst/src/main/java/com/vitorpamplona/amethyst/model/Account.kt

@@ -167,11 +167,11 @@ import com.vitorpamplona.quartz.nip03Timestamp.OtsResolver
 import com.vitorpamplona.quartz.nip04Dm.PrivateDMCache
 import com.vitorpamplona.quartz.nip04Dm.messages.PrivateDmEvent
 import com.vitorpamplona.quartz.nip09Deletions.DeletionEvent
-import com.vitorpamplona.quartz.nip10Notes.BaseThreadedEvent
 import com.vitorpamplona.quartz.nip10Notes.TextNoteEvent
 import com.vitorpamplona.quartz.nip10Notes.content.findHashtags
 import com.vitorpamplona.quartz.nip10Notes.content.findNostrUris
 import com.vitorpamplona.quartz.nip10Notes.content.findURLs
+import com.vitorpamplona.quartz.nip10Notes.threadRootIdOrSelf
 import com.vitorpamplona.quartz.nip17Dm.NIP17Factory
 import com.vitorpamplona.quartz.nip17Dm.base.NIP17Group
 import com.vitorpamplona.quartz.nip17Dm.files.ChatMessageEncryptedFileHeaderEvent
@@ -2838,17 +2838,16 @@ class Account(
     }
 
     suspend fun muteThread(rootHex: HexKey) {
+        if (isThreadMuted(rootHex)) return
         sendMyPublicAndPrivateOutbox(muteList.hideThread(rootHex))
     }
 
     suspend fun unmuteThread(rootHex: HexKey) {
+        if (!isThreadMuted(rootHex)) return
         muteList.showThread(rootHex)?.let { sendMyPublicAndPrivateOutbox(it) }
     }
 
-    fun resolveThreadRoot(note: Note): HexKey {
+    fun resolveThreadRoot(note: Note): HexKey = note.event?.threadRootIdOrSelf() ?: note.idHex
-        val ev = note.event
-        return (ev as? BaseThreadedEvent)?.root()?.eventId ?: note.idHex
-    }
 
     fun isThreadMuted(rootHex: HexKey): Boolean = hiddenUsers.flow.value.isThreadMuted(rootHex)
 
@@ -2986,7 +2985,8 @@ class Account(
     }
 
     override fun isAcceptable(note: Note): Boolean {
-        if (isThreadMuted(resolveThreadRoot(note))) return false
+        val mutedThreads = hiddenUsers.flow.value.mutedThreads
+        if (mutedThreads.isNotEmpty() && mutedThreads.contains(resolveThreadRoot(note))) return false
         return note.author?.let { isAcceptable(it) } ?: true &&
             // if user hasn't hided this author
             isAcceptableDirect(note) &&

amethyst/src/main/java/com/vitorpamplona/amethyst/ui/dal/FilterByListParams.kt

@@ -31,7 +31,7 @@ import com.vitorpamplona.quartz.nip01Core.core.Event
 import com.vitorpamplona.quartz.nip01Core.core.HexKey
 import com.vitorpamplona.quartz.nip01Core.relay.normalizer.NormalizedRelayUrl
 import com.vitorpamplona.quartz.nip01Core.tags.hashtags.countHashtags
-import com.vitorpamplona.quartz.nip10Notes.BaseThreadedEvent
+import com.vitorpamplona.quartz.nip10Notes.threadRootIdOrSelf
 import com.vitorpamplona.quartz.nip51Lists.muteList.MuteListEvent
 import com.vitorpamplona.quartz.nip51Lists.peopleList.PeopleListEvent
 import com.vitorpamplona.quartz.utils.TimeUtils
@@ -46,8 +46,7 @@ class FilterByListParams(
 
     fun isNotInMutedThread(noteEvent: Event): Boolean {
         if (hiddenLists.mutedThreads.isEmpty()) return true
-        val rootId = (noteEvent as? BaseThreadedEvent)?.root()?.eventId ?: noteEvent.id
+        return !hiddenLists.mutedThreads.contains(noteEvent.threadRootIdOrSelf())
-        return !hiddenLists.mutedThreads.contains(rootId)
     }
 
     fun isNotInTheFuture(noteEvent: Event) = noteEvent.createdAt <= now

amethyst/src/main/java/com/vitorpamplona/amethyst/ui/screen/loggedIn/notifications/dal/NotificationFeedFilter.kt

@@ -225,11 +225,8 @@ class NotificationFeedFilter(
                 }
             }
 
-        // Drop reactions/zaps/reposts whose target post is in a muted thread.
+        // Reactions/zaps/reposts target a note via `replyTo`, not via thread-root tags,
-        // The inner-note renderer would otherwise show a misleading
+        // so isNotInMutedThread on the wrapper event misses them.
-        // "This post was hidden because it mentions your hidden users or words"
-        // placeholder for muted-thread targets (regression from Task 6's
-        // Note.isHiddenFor extension).
         if (noteEvent is ReactionEvent || noteEvent is LnZapEvent ||
             noteEvent is RepostEvent || noteEvent is GenericRepostEvent
         ) {

amethyst/src/main/java/com/vitorpamplona/amethyst/ui/screen/loggedIn/settings/dal/MutedThreadsFeedFilter.kt

@@ -34,6 +34,6 @@ class MutedThreadsFeedFilter(
 
     override fun feed(): List<Note> =
         account.hiddenUsers.flow.value.mutedThreads
-            .mapNotNull { LocalCache.getNoteIfExists(it) ?: LocalCache.getOrCreateNote(it) }
+            .map { LocalCache.getOrCreateNote(it) }
             .sortedByDescending { it.createdAt() }
 }

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/model/Note.kt

@@ -39,6 +39,7 @@ import com.vitorpamplona.quartz.nip01Core.relay.normalizer.NormalizedRelayUrl
 import com.vitorpamplona.quartz.nip01Core.tags.hashtags.anyHashTag
 import com.vitorpamplona.quartz.nip01Core.tags.publishedAt.PublishedAtProvider
 import com.vitorpamplona.quartz.nip10Notes.BaseThreadedEvent
+import com.vitorpamplona.quartz.nip10Notes.threadRootIdOrSelf
 import com.vitorpamplona.quartz.nip18Reposts.GenericRepostEvent
 import com.vitorpamplona.quartz.nip18Reposts.RepostEvent
 import com.vitorpamplona.quartz.nip19Bech32.entities.NAddress
@@ -860,10 +861,10 @@ open class Note(
             return true
         }
 
-        // if this note belongs to a muted thread (by NIP-10 root id)
+        if (accountChoices.mutedThreads.isNotEmpty() &&
-        if (accountChoices.mutedThreads.isNotEmpty()) {
+            accountChoices.mutedThreads.contains(thisEvent.threadRootIdOrSelf())
-            val rootId = (thisEvent as? BaseThreadedEvent)?.root()?.eventId ?: idHex
+        ) {
-            if (accountChoices.mutedThreads.contains(rootId)) return true
+            return true
         }
 
         // if the post is sensitive and the user doesn't want to see sensitive content

commons/src/commonTest/kotlin/com/vitorpamplona/amethyst/commons/model/NoteIsHiddenForTest.kt

@@ -25,22 +25,11 @@ import kotlin.test.Test
 import kotlin.test.assertFalse
 import kotlin.test.assertTrue
 
-/**
- * Unit tests for Note.isHiddenFor() focusing on the mutedThreads check.
- *
- * Fixture approach:
- * - TextNoteEvent is constructed directly via its primary constructor (no signing needed —
- *   the sig field is not validated in isHiddenFor).
- * - A Note is created with the event's id, then note.event is set.
- * - LiveHiddenUsers is a plain data class — no Android plumbing required.
- */
 class NoteIsHiddenForTest {
-    // 64-char hex constants
     private val rootId = "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
     private val replyId = "bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb"
     private val authorPubKey = "cccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccc"
 
-    // Minimal LiveHiddenUsers with all filters off (used as a baseline)
     private val noHidden =
         LiveHiddenUsers(
             showSensitiveContent = null,
@@ -50,12 +39,6 @@ class NoteIsHiddenForTest {
             mutedThreads = emptySet(),
         )
 
-    /**
-     * Build a TextNoteEvent.
-     *
-     * @param id The event id (64 hex chars).
-     * @param eTags Raw `e` tag arrays included in the event's tags.
-     */
     private fun textNoteEvent(
         id: String,
         pubKey: String = authorPubKey,
@@ -69,21 +52,12 @@ class NoteIsHiddenForTest {
         sig = "sig",
     )
 
-    /** A marked `e` tag array with marker="root" at index 3. */
     private fun rootETag(eventId: String) = arrayOf("e", eventId, "", "root")
 
-    // -------------------------------------------------------------------------
-
     @Test
     fun reply_inMutedThread_isHidden() {
-        // A reply whose NIP-10 root points to `rootId`, which is muted.
+        val event = textNoteEvent(id = replyId, eTags = arrayOf(rootETag(rootId)))
-        val event =
-            textNoteEvent(
-                id = replyId,
-                eTags = arrayOf(rootETag(rootId)),
-            )
         val note = Note(replyId).also { it.event = event }
-
         val choices = noHidden.copy(mutedThreads = setOf(rootId))
 
         assertTrue(note.isHiddenFor(choices), "Reply inside a muted thread must be hidden")
@@ -91,14 +65,8 @@ class NoteIsHiddenForTest {
 
     @Test
     fun topLevelNote_ownIdMuted_isHidden() {
-        // A top-level note (no e-tags) whose own id is in mutedThreads.
+        val event = textNoteEvent(id = rootId, eTags = emptyArray())
-        val event =
-            textNoteEvent(
-                id = rootId,
-                eTags = emptyArray(),
-            )
         val note = Note(rootId).also { it.event = event }
-
         val choices = noHidden.copy(mutedThreads = setOf(rootId))
 
         assertTrue(note.isHiddenFor(choices), "Top-level note whose id is muted must be hidden")
@@ -106,16 +74,9 @@ class NoteIsHiddenForTest {
 
     @Test
     fun note_inUnmutedThread_isNotHidden() {
-        // A reply note whose root is NOT in mutedThreads, author not hidden.
         val otherRoot = "dddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddddd"
-        val event =
+        val event = textNoteEvent(id = replyId, eTags = arrayOf(rootETag(otherRoot)))
-            textNoteEvent(
-                id = replyId,
-                eTags = arrayOf(rootETag(otherRoot)),
-            )
         val note = Note(replyId).also { it.event = event }
-
-        // rootId is muted, but this note's root is otherRoot
         val choices = noHidden.copy(mutedThreads = setOf(rootId))
 
         assertFalse(note.isHiddenFor(choices), "Reply in an un-muted thread must not be hidden")
@@ -123,15 +84,9 @@ class NoteIsHiddenForTest {
 
     @Test
     fun authorHidden_isHidden_regression() {
-        // Regression guard: author-hidden notes must still return true.
         val event = textNoteEvent(id = replyId)
         val note = Note(replyId).also { it.event = event }
-
+        val choices = noHidden.copy(hiddenUsersHashCodes = setOf(authorPubKey.hashCode()))
-        // Put the author's pubKey hashCode into hiddenUsersHashCodes
-        val choices =
-            noHidden.copy(
-                hiddenUsersHashCodes = setOf(authorPubKey.hashCode()),
-            )
 
         assertTrue(note.isHiddenFor(choices), "Note whose author is hidden must still be hidden")
     }

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

@@ -22,6 +22,7 @@ package com.vitorpamplona.quartz.nip10Notes
 
 import androidx.compose.runtime.Immutable
 import com.vitorpamplona.quartz.experimental.nipsOnNostr.NipTextEvent
+import com.vitorpamplona.quartz.nip01Core.core.Event
 import com.vitorpamplona.quartz.nip01Core.core.HexKey
 import com.vitorpamplona.quartz.nip01Core.tags.aTag.taggedATags
 import com.vitorpamplona.quartz.nip01Core.tags.people.taggedUsers
@@ -30,6 +31,8 @@ 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
+
 @Immutable
 open class BaseThreadedEvent(
     id: HexKey,