From 8b632c9b05ca725a7714bfdef462afae6512d8fb Mon Sep 17 00:00:00 2001
From: Nikola Hristov <139394063+iexavl@users.noreply.github.com>
Date: Mon, 31 Aug 2026 21:52:19 +0300
Subject: [PATCH] gh-15182: Fix tab changing when handling tab close when group
 collapses (gh-15183)

---
 src/zen/split-view/ZenViewSplitter.mjs | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/src/zen/split-view/ZenViewSplitter.mjs b/src/zen/split-view/ZenViewSplitter.mjs
index 7b5f9ce1c..e464e16cd 100644
--- a/src/zen/split-view/ZenViewSplitter.mjs
+++ b/src/zen/split-view/ZenViewSplitter.mjs
@@ -160,7 +160,9 @@ class nsZenViewSplitter extends nsZenDOMOperatedFeature {
     if (groupIndex < 0) {
       return;
     }
-    this.removeTabFromGroup(tab, groupIndex, { forUnsplit: true });
+    this.removeTabFromGroup(tab, groupIndex, {
+      forUnsplit: true,
+    });
   }
 
   /**
@@ -203,16 +205,21 @@ class nsZenViewSplitter extends nsZenDOMOperatedFeature {
    * @param {object} [options={}] - Additional options.
    * @param {boolean} [options.forUnsplit=false] - Whether the removal is for unsplitting.
    * @param {boolean} [options.dontRebuildGrid=false] - Whether to skip rebuilding the grid layout.
-   * @param {boolean} [options.changeTab=true] - Whether to change the selected tab.
+   * @param {boolean} [options.changeTab=undefined] - Whether to change the selected tab. If left unspecified,
+   * change the selected tab only if the current view is the group the removed tab was in.
    */
   removeTabFromGroup(
     tab,
     groupIndex = undefined,
-    { forUnsplit = false, dontRebuildGrid = false, changeTab = true } = {}
+    { forUnsplit = false, dontRebuildGrid = false, changeTab = undefined } = {}
   ) {
     if (typeof groupIndex === "undefined") {
       groupIndex = this._data.findIndex(group => group.tabs.includes(tab));
     }
+
+    if (typeof changeTab === "undefined") {
+      changeTab = groupIndex === this.currentView;
+    }
     // If groupIndex === -1, so `this._data.findIndex` couldn't find the split group
     if (groupIndex < 0) {
       return;