fix(settings): conditional refilter on save — preserve chat history for cosmetic changes

Settings.Save() unconditionally ran ClearAllTabs + FilterAllTabsAsync
after every save. The cycle reloads messages from the DB, which silently
wipes any in-session message that wasn't persisted — Privacy-First
configurations block most channels from the DB, so all unlogged
channels (Allgemein/Say/Yell/Shout under default filters) showed up
empty after every settings save.

New HasFilterRelevantChanges helper compares Mutable to Plugin.Config
across:
- PrivacyFilterEnabled
- PrivacyPersistChannels (HashSet<ChatType>)
- PrivacyPersistUnknownChannels
- FilterIncludePreviousSessions
- per-persistent-tab: Identifier (reorder/swap), SelectedChannels,
  ExtraChatAll, ExtraChatChannels

Refilter only runs if any of those changed. Cosmetic settings (theme,
tab icons, layout, fonts, language) leave the chat log untouched.
Combined with the prior UpdateFrom Identifier-mapping fix and the
TempTab skip in ClearAllTabs/FilterAllTabs, both persistent and
Auto-Tell tabs now fully survive a settings save.

Reported by Flo from in-game testing 2026-05-05/06: 'der allgemein
chat tab z.b immernoch gecleart wird' / 'alle vom plugin nicht
geloggten channel sind dann leer'.

Also updated yaml changelog, docs/CHANGELOG.md and .github/forge-posts/
v1.2.0.md to describe the actual fix shape rather than the partial
UpdateFrom-only fix that preceded it.

HellionChat/HellionChat.yaml

@@ -114,13 +114,15 @@ changelog: |-
 
   Bug fixes from in-game testing:
 
-  - Settings save no longer wipes the in-session chat history of
-    persistent tabs (Tab.Clone preserved Identifier but not
-    Messages — Identifier-based mapping now restores the live
-    MessageList onto cloned tabs).
-  - Settings save no longer clears Auto-Tell tabs either
-    (ClearAllTabs/FilterAllTabs now skip TempTabs since their
-    messages have no DB persistence to refilter from).
+  - Settings save no longer wipes chat history by default. The
+    heavy ClearAllTabs + FilterAllTabsAsync refilter cycle now
+    only runs when a filter-relevant setting actually changed
+    (Privacy filter, persisted channels, per-tab channel
+    selection). Cosmetic changes — theme, tab icons, layout
+    flags — keep the in-session chat intact. Combined with an
+    Identifier-based MessageList restore in Configuration.
+    UpdateFrom and a TempTab skip in ClearAllTabs/FilterAllTabs,
+    persistent tabs and Auto-Tell tabs both survive the save.
   - Sidebar buttons now align vertically with the first message
     row (top padding mirrors the chat header toolbar height).
   - Sidebar child window no longer paints the top padding with

HellionChat/Ui/Settings.cs

@@ -210,14 +210,24 @@ public sealed class SettingsWindow : Dalamud.Interface.Windowing.Window
         var fontSizeChanged = Math.Abs(Mutable.SymbolsFontSizeV2 - Plugin.Config.SymbolsFontSizeV2) > 0.001
                           || Math.Abs(Mutable.FontSizeV2 - Plugin.Config.FontSizeV2) > 0.001;
         var italicStateChanged = Mutable.ItalicEnabled != Plugin.Config.ItalicEnabled;
+        // v1.2.0 — Refilter only if a filter-relevant setting actually
+        // changed. The Clear+Refilter cycle reloads messages from the DB,
+        // which silently wipes any in-session message that wasn't
+        // persisted (Privacy-First config blocks most channels from DB).
+        // Cosmetic changes (theme, tab icons, layout flags) trigger no
+        // refilter — chat history stays intact.
+        var filtersChanged = HasFilterRelevantChanges();
 
         Plugin.Config.UpdateFrom(Mutable, true);
 
         // save after 60 frames have passed, which should hopefully not
         // commit any changes that cause a crash
         Plugin.DeferredSaveFrames = 60;
-        Plugin.MessageManager.ClearAllTabs();
-        Plugin.MessageManager.FilterAllTabsAsync();
+        if (filtersChanged)
+        {
+            Plugin.MessageManager.ClearAllTabs();
+            Plugin.MessageManager.FilterAllTabsAsync();
+        }
 
         if (fontChanged || fontSizeChanged || italicStateChanged)
             Plugin.FontManager.BuildFonts();
@@ -233,4 +243,59 @@ public sealed class SettingsWindow : Dalamud.Interface.Windowing.Window
 
         Initialise();
     }
+
+    /// <summary>
+    /// v1.2.0 — Detects whether any setting that influences message
+    /// filtering changed between Plugin.Config and the Mutable working
+    /// copy. Used to gate the heavy ClearAllTabs+FilterAllTabsAsync cycle
+    /// in Save: cosmetic changes (theme, tab icons, layout flags) do not
+    /// touch the chat log, only filter-relevant changes do. Without this
+    /// gate, every settings save wipes the chat history of any channel
+    /// the Privacy filter blocks from being persisted to the DB —
+    /// reported by Flo from in-game testing 2026-05-05/06.
+    /// </summary>
+    private bool HasFilterRelevantChanges()
+    {
+        // Top-level privacy controls.
+        if (Mutable.PrivacyFilterEnabled != Plugin.Config.PrivacyFilterEnabled) return true;
+        if (Mutable.PrivacyPersistUnknownChannels != Plugin.Config.PrivacyPersistUnknownChannels) return true;
+        if (!Mutable.PrivacyPersistChannels.SetEquals(Plugin.Config.PrivacyPersistChannels)) return true;
+
+        // FilterIncludePreviousSessions changes the GetMostRecentMessages
+        // window in MessageManager.FilterAllTabs and is therefore filter-
+        // relevant even though it lives outside the Privacy block.
+        if (Mutable.FilterIncludePreviousSessions != Plugin.Config.FilterIncludePreviousSessions) return true;
+
+        // Per-tab channel selection. Compare persistent tabs only —
+        // TempTabs are session-only and never refiltered anyway.
+        var origPersistent = Plugin.Config.Tabs.Where(t => !t.IsTempTab).ToList();
+        var newPersistent = Mutable.Tabs.Where(t => !t.IsTempTab).ToList();
+
+        if (origPersistent.Count != newPersistent.Count) return true; // add or delete
+
+        for (var i = 0; i < origPersistent.Count; i++)
+        {
+            var orig = origPersistent[i];
+            var neu = newPersistent[i];
+
+            // Identifier mismatch at the same index means reorder or
+            // a slot got swapped — treat as filter-relevant so the new
+            // channel-selection layout actually applies.
+            if (orig.Identifier != neu.Identifier) return true;
+
+            if (orig.ExtraChatAll != neu.ExtraChatAll) return true;
+            if (!orig.ExtraChatChannels.SetEquals(neu.ExtraChatChannels)) return true;
+
+            // SelectedChannels is a Dictionary<ChatType, (ChatSource, ChatSource)>
+            // — value-tuple equality already does the right thing per-pair.
+            if (orig.SelectedChannels.Count != neu.SelectedChannels.Count) return true;
+            foreach (var pair in orig.SelectedChannels)
+            {
+                if (!neu.SelectedChannels.TryGetValue(pair.Key, out var nv)) return true;
+                if (!pair.Value.Equals(nv)) return true;
+            }
+        }
+
+        return false;
+    }
 }