diff --git a/toolkit/content/widgets/tabbrowser.xml b/toolkit/content/widgets/tabbrowser.xml
index 9f30a2be2ebe..b477e2202b4d 100644
--- a/toolkit/content/widgets/tabbrowser.xml
+++ b/toolkit/content/widgets/tabbrowser.xml
@@ -370,6 +370,9 @@
                   aWebProgress.isLoadingDocument)
                 this.mTabBrowser.setIcon(this.mTab, null);
 
+              // changing location, clear out the missing plugins list
+              this.mTab.missingPlugins = null;
+
               if (!this.mBlank && this.mTabBrowser.mCurrentTab == this.mTab) {
                 for (var i = 0; i < this.mTabBrowser.mProgressListeners.length; i++) {
                   var p = this.mTabBrowser.mProgressListeners[i];