2 files changed, 2 insertions, 2 deletions
diff --git a/toolkit/components/alerts/resources/content/alert.js b/toolkit/components/alerts/resources/content/alert.js
index ce60ab0fa9..12068b5488 100644
--- a/toolkit/components/alerts/resources/content/alert.js
+++ b/toolkit/components/alerts/resources/content/alert.js
@@ -313,6 +313,7 @@ function onAlertClick() {
   let alertBox = document.getElementById("alertBox");
   if (alertBox.getAttribute("animate") == "true") {
     // Closed when the animation ends.
+    alertBox.style.animationDuration = ".6s";
     alertBox.setAttribute("clicked", "true");
   } else {
     window.close();
@@ -355,6 +356,7 @@ function onAlertClose() {
   let alertBox = document.getElementById("alertBox");
   if (alertBox.getAttribute("animate") == "true") {
     // Closed when the animation ends.
+    alertBox.style.animationDuration = ".6s";
     alertBox.setAttribute("closing", "true");
   } else {
     window.close();
diff --git a/toolkit/themes/shared/alert-common.css b/toolkit/themes/shared/alert-common.css
index 010e89393d..17510c0dbd 100644
--- a/toolkit/themes/shared/alert-common.css
+++ b/toolkit/themes/shared/alert-common.css
@@ -15,14 +15,12 @@
 }
 
 #alertBox[animate][clicked] {
-  animation-duration: .6s;
   animation-name: alert-clicked-animation;
 }
 
 /* This is used if the close button is clicked
    before the animation has finished. */
 #alertBox[animate][closing] {
-  animation-duration: .6s;
   animation-name: alert-closing-animation;
 }