diff --git a/browser/base/content/tabbrowser.js b/browser/base/content/tabbrowser.js
index 8beafa99e20f..d52ff9c29d7a 100644
--- a/browser/base/content/tabbrowser.js
+++ b/browser/base/content/tabbrowser.js
@@ -2587,7 +2587,7 @@ window._gBrowser = {
   removeTabs(tabs) {
     let tabsWithBeforeUnload = [];
     let lastToClose;
-    let aParams = {animation: true};
+    let aParams = { animate: true };
     for (let tab of tabs) {
       if (tab.selected)
         lastToClose = tab;