From e474f1df3ab0c7e7d271011ae49f3eea494eb3f7 Mon Sep 17 00:00:00 2001
From: Brandon Quon <147013549+bnquon@users.noreply.github.com>
Date: Mon, 27 Jul 2026 05:48:18 -0700
Subject: [PATCH] gh-14726: Fix essential tab reordering at maximum capacity
 (gh-14729)

---
 src/zen/tabs/ZenPinnedTabManager.mjs | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/zen/tabs/ZenPinnedTabManager.mjs b/src/zen/tabs/ZenPinnedTabManager.mjs
index 40f25ab85..7f4c48cf5 100644
--- a/src/zen/tabs/ZenPinnedTabManager.mjs
+++ b/src/zen/tabs/ZenPinnedTabManager.mjs
@@ -1019,12 +1019,15 @@ class nsZenPinnedTabManager extends nsZenDOMOperatedFeature {
   }
 
   canEssentialBeAdded(tab) {
+    const isExistingEssentialTab = tab.hasAttribute("zen-essential");
     return (
       !(
         (tab.getAttribute("usercontextid") || 0) !=
           (gZenWorkspaces.getActiveWorkspaceFromCache().containerTabId || 0) &&
         gZenWorkspaces.containerSpecificEssentials
-      ) && gBrowser._numZenEssentials < this.maxEssentialTabs
+      ) &&
+      (isExistingEssentialTab ||
+        gBrowser._numZenEssentials < this.maxEssentialTabs)
     );
   }