diff --git a/browser/themes/pinstripe/browser/browser.css b/browser/themes/pinstripe/browser/browser.css
index 0bbe7a9a5046..11e2bdeb65e6 100755
--- a/browser/themes/pinstripe/browser/browser.css
+++ b/browser/themes/pinstripe/browser/browser.css
@@ -1251,7 +1251,7 @@ tabpanels.plain {
 }
 
 .toolbar-drop-indicator-bar {
-  display: none;
+  visibility: hidden;
   height: 16px;
   margin-bottom: -16px;
   margin-left: 4px;
@@ -1259,7 +1259,7 @@ tabpanels.plain {
 }
 
 .toolbar-drop-indicator-bar[dragging="true"] {
-  display: -moz-box;
+  visibility: visible;
 }
 
 toolbarbutton.bookmark-item[dragover="true"][open="true"] {
diff --git a/browser/themes/winstripe/browser/browser.css b/browser/themes/winstripe/browser/browser.css
index a0eed69c94ed..e70f03ae572d 100644
--- a/browser/themes/winstripe/browser/browser.css
+++ b/browser/themes/winstripe/browser/browser.css
@@ -1427,7 +1427,7 @@ toolbar[mode="text"] > #window-controls > toolbarbutton > .toolbarbutton-text {
 }
 
 .toolbar-drop-indicator-bar {
-  display: none;
+  visibility: hidden;
   height: 16px;
   margin-bottom: -16px;
   margin-left: 4px;
@@ -1435,7 +1435,7 @@ toolbar[mode="text"] > #window-controls > toolbarbutton > .toolbarbutton-text {
 }
 
 .toolbar-drop-indicator-bar[dragging="true"] {
-  display: -moz-box;
+  visibility: visible;
 }
 
 toolbarbutton.bookmark-item[dragover="true"][open="true"] {
diff --git a/toolkit/themes/pinstripe/global/browser.css b/toolkit/themes/pinstripe/global/browser.css
index d908667e94b6..f1ee3dd828db 100644
--- a/toolkit/themes/pinstripe/global/browser.css
+++ b/toolkit/themes/pinstripe/global/browser.css
@@ -169,7 +169,7 @@ tabbrowser > tabbox > tabpanels {
 }
 
 .tab-drop-indicator-bar {
-   display:none;
+   visibility: hidden;
    height: 9px;
    margin-top: -9px;
    position: relative;
@@ -184,7 +184,7 @@ tabbrowser > tabbox > tabpanels {
 }
 
 .tab-drop-indicator-bar[dragging="true"] {
-   display: -moz-box;
+   visibility: visible;
 }
 
 /**
diff --git a/toolkit/themes/winstripe/global/browser.css b/toolkit/themes/winstripe/global/browser.css
index d8a240c51803..55a91148fe4b 100644
--- a/toolkit/themes/winstripe/global/browser.css
+++ b/toolkit/themes/winstripe/global/browser.css
@@ -157,7 +157,7 @@ tabpanels {
  */
 
 .tab-drop-indicator-bar {
-    display:none;
+    visibility: hidden;
     height: 9px;
     margin-top: -9px;
     position: relative;
@@ -172,7 +172,7 @@ tabpanels {
 }
 
 .tab-drop-indicator-bar[dragging="true"] {
-    display: -moz-box;
+    visibility: visible;
 }
 
 /**