From 3850f52401a3de6f6f8641ea0c97c3720d6daae1 Mon Sep 17 00:00:00 2001
From: zadam <zadam.apps@gmail.com>
Date: Sat, 20 Jul 2019 22:01:50 +0200
Subject: [PATCH] add ResizeObserver to tabs with fallback for older firefox

---
 src/public/javascripts/services/tab_row.js | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/src/public/javascripts/services/tab_row.js b/src/public/javascripts/services/tab_row.js
index 915e84643..9ade26e2e 100644
--- a/src/public/javascripts/services/tab_row.js
+++ b/src/public/javascripts/services/tab_row.js
@@ -69,10 +69,19 @@ class TabRow {
     }
 
     setupEvents() {
-        window.addEventListener('resize', _ => {
+        const resizeListener = _ => {
             this.cleanUpPreviouslyDraggedTabs();
             this.layoutTabs();
-        });
+        };
+
+        // ResizeObserver exists only in FF69
+        if (typeof ResizeObserver !== "undefined") {
+            new ResizeObserver(resizeListener).observe(this.el);
+        }
+        else {
+            // for older firefox
+            window.addEventListener('resize', resizeListener);
+        }
 
         this.tabEls.forEach((tabEl) => this.setTabCloseEventListener(tabEl));
     }