From 1a1804d2be67903a003085ff393d4b1db391420f Mon Sep 17 00:00:00 2001
From: "mr. m" <mr.m@tuta.com>
Date: Fri, 27 Feb 2026 13:12:28 +0100
Subject: [PATCH] feat: Properly animate tab addition to collapsed live
 folders, b=no-bug, c=folders

---
 src/zen/folders/ZenFolder.mjs  | 15 +++++++++------
 src/zen/folders/ZenFolders.mjs |  2 +-
 2 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/src/zen/folders/ZenFolder.mjs b/src/zen/folders/ZenFolder.mjs
index 56605baba..98c9b3f23 100644
--- a/src/zen/folders/ZenFolder.mjs
+++ b/src/zen/folders/ZenFolder.mjs
@@ -284,12 +284,15 @@ export class nsZenFolder extends MozTabbrowserTabGroup {
       let activeTabs = this.activeTabs;
       activeTabs.push(...tabs);
       gZenFolders._dontAnimateFolder = true;
-      this.collapsed = false;
-      for (let tab of activeTabs) {
-        tab.setAttribute("folder-active", "true");
-      }
-      this.collapsed = true;
-      delete gZenFolders._dontAnimateFolder;
+      gZenFolders.on_TabGroupExpand({ target: this }).then(() => {
+        for (let tab of activeTabs) {
+          tab.setAttribute("folder-active", "true");
+        }
+        gZenFolders.on_TabGroupCollapse({ target: this }).then(() => {
+          delete gZenFolders._dontAnimateFolder;
+          gBrowser.tabContainer._invalidateCachedVisibleTabs();
+        });
+      });
     }
   }
 
diff --git a/src/zen/folders/ZenFolders.mjs b/src/zen/folders/ZenFolders.mjs
index cef5cc4f3..ed99a920a 100644
--- a/src/zen/folders/ZenFolders.mjs
+++ b/src/zen/folders/ZenFolders.mjs
@@ -1533,7 +1533,7 @@ class nsZenFolders extends nsZenDOMOperatedFeature {
     this.#animationCount += 1;
     await Promise.all(animations);
     this.#animationCount -= 1;
-    gBrowser.tabContainer._invalidateCachedTabs();
+    gBrowser.tabContainer._invalidateCachedVisibleTabs();
   }
 
   async animateUnload(group, tabToUnload, ungroup = false) {