--- a/toolkit/themes/gnomestripe/mozapps/extensions/extensions.css
+++ b/toolkit/themes/gnomestripe/mozapps/extensions/extensions.css
@@ -37,16 +37,20 @@
 
 #commandBarBottom button .button-icon {
   margin-top: 0px;
   margin-bottom: 0px;
   -moz-margin-start: 0px;
   -moz-margin-end: 5px;
 }
 
+#checkUpdatesAllButton {
+  list-style-image: none;
+}
+
 #installFileButton, #installUpdatesAllButton {
   -moz-image-region: rect(0px, 84px, 21px, 63px);
 }
 
 #installFileButton[disabled="true"],
 #installUpdatesAllButton[disabled="true"] {
   -moz-image-region: rect(21px, 84px, 42px, 63px);
 }

--- a/toolkit/themes/winstripe/mozapps/extensions/extensions.css
+++ b/toolkit/themes/winstripe/mozapps/extensions/extensions.css
@@ -36,16 +36,20 @@
 
 #commandBarBottom button .button-icon {
   margin-top: 0px;
   margin-bottom: 0px;
   -moz-margin-start: 0px;
   -moz-margin-end: 5px;
 }
 
+#checkUpdatesAllButton {
+  list-style-image: none;
+}
+
 #installFileButton, #installUpdatesAllButton {
   -moz-image-region: rect(0px, 84px, 21px, 63px);
 }
 
 #installFileButton[disabled="true"],
 #installUpdatesAllButton[disabled="true"] {
   -moz-image-region: rect(21px, 84px, 42px, 63px);
 }