--- a/devtools/client/responsive.html/browser/tunnel.js
+++ b/devtools/client/responsive.html/browser/tunnel.js
@@ -335,16 +335,18 @@ MessageManagerTunnel.prototype = {
     "Content:StatusChange",
     // Messages sent to remote-browser.xml
     "DOMTitleChanged",
     "ImageDocumentLoaded",
     "Forms:ShowDropDown",
     "Forms:HideDropDown",
     "InPermitUnload",
     "PermitUnload",
+    // Messages sent to tabbrowser.xml
+    "contextmenu",
     // Messages sent to SelectParentHelper.jsm
     "Forms:UpdateDropDown",
     // Messages sent to browser.js
     "PageVisibility:Hide",
     "PageVisibility:Show",
     // Messages sent to SessionStore.jsm
     "SessionStore:update",
     // Messages sent to BrowserTestUtils.jsm