--- a/browser/base/content/browser-sets.inc
+++ b/browser/base/content/browser-sets.inc
@@ -20,17 +20,17 @@
     <command id="cmd_handleBackspace" oncommand="BrowserHandleBackspace();" />
     <command id="cmd_handleShiftBackspace" oncommand="BrowserHandleShiftBackspace();" />
 
     <command id="cmd_newNavigatorTab" oncommand="BrowserOpenNewTabOrWindow(event);"/>
     <command id="Browser:OpenFile"  oncommand="BrowserOpenFileWindow();"/>
     <command id="Browser:SavePage" oncommand="saveDocument(gBrowser.selectedBrowser.contentDocumentAsCPOW);"/>
 
     <command id="Browser:SendLink"
-             oncommand="MailIntegration.sendLinkForWindow(window.content);"/>
+             oncommand="MailIntegration.sendLinkForBrowser(gBrowser.selectedBrowser);"/>
 
     <command id="cmd_pageSetup" oncommand="PrintUtils.showPageSetup();"/>
     <command id="cmd_print" oncommand="PrintUtils.print(window.gBrowser.selectedBrowser.contentWindowAsCPOW, window.gBrowser.selectedBrowser);"/>
     <command id="cmd_printPreview" oncommand="PrintUtils.printPreview(PrintPreviewListener);"/>
     <command id="cmd_close" oncommand="BrowserCloseTabOrWindow()"/>
     <command id="cmd_closeWindow" oncommand="BrowserTryToCloseWindow()"/>
     <command id="cmd_CustomizeToolbars" oncommand="BrowserCustomizeToolbar()"/>
     <command id="cmd_quitApplication" oncommand="goQuitApplication()"/>

--- a/browser/base/content/browser.js
+++ b/browser/base/content/browser.js
@@ -1733,17 +1733,17 @@ function HandleAppCommandEvent(evt) {
   case "Print":
     PrintUtils.print(gBrowser.selectedBrowser.contentWindowAsCPOW,
                      gBrowser.selectedBrowser);
     break;
   case "Save":
     saveDocument(gBrowser.selectedBrowser.contentDocumentAsCPOW);
     break;
   case "SendMail":
-    MailIntegration.sendLinkForWindow(window.content);
+    MailIntegration.sendLinkForBrowser(gBrowser.selectedBrowser);
     break;
   default:
     return;
   }
   evt.stopPropagation();
   evt.preventDefault();
 }
 
@@ -6519,19 +6519,18 @@ function warnAboutClosingWindow() {
   // closing multiple tabs.
   return isPBWindow || gBrowser.warnAboutClosingTabs(gBrowser.closingTabsEnum.ALL);
 #else
   return true;
 #endif
 }
 
 var MailIntegration = {
-  sendLinkForWindow: function (aWindow) {
-    this.sendMessage(aWindow.location.href,
-                     aWindow.document.title);
+  sendLinkForBrowser: function (aBrowser) {
+    this.sendMessage(aBrowser.currentURI.spec, aBrowser.contentTitle);
   },
 
   sendMessage: function (aBody, aSubject) {
     // generate a mailto url based on the url and the url's title
     var mailtoUrl = "mailto:";
     if (aBody) {
       mailtoUrl += "?body=" + encodeURIComponent(aBody);
       mailtoUrl += "&subject=" + encodeURIComponent(aSubject);

--- a/browser/components/customizableui/CustomizableWidgets.jsm
+++ b/browser/components/customizableui/CustomizableWidgets.jsm
@@ -915,17 +915,17 @@ const CustomizableWidgets = [
         this.charsetInfo = CharsetMenu.getData();
       }
     }
   }, {
     id: "email-link-button",
     tooltiptext: "email-link-button.tooltiptext3",
     onCommand: function(aEvent) {
       let win = aEvent.view;
-      win.MailIntegration.sendLinkForWindow(win.content);
+      win.MailIntegration.sendLinkForBrowser(win.gBrowser.selectedBrowser)
     }
   }, {
     id: "loop-button",
     type: "custom",
     label: "loop-call-button3.label",
     tooltiptext: "loop-call-button3.tooltiptext",
     defaultArea: CustomizableUI.AREA_NAVBAR,
     introducedInVersion: 4,