--- a/devtools/client/inspector/inspector.js
+++ b/devtools/client/inspector/inspector.js
@@ -1836,16 +1836,19 @@ if (url.search.length > 1) {
 
   const { Selection } = require("devtools/client/framework/selection");
   const { InspectorFront } = require("devtools/shared/fronts/inspector");
   const { getHighlighterUtils } = require("devtools/client/framework/toolbox-highlighter-utils");
 
   Task.spawn(function* () {
     let target = yield targetFromURL(url);
 
+    let notImplemented = function () {
+      throw new Error("Not implemented in a tab");
+    };
     let fakeToolbox = {
       target,
       hostType: "bottom",
       doc: window.document,
       win: window,
       on() {}, emit() {}, off() {},
       initInspector() {},
       browserRequire: BrowserLoader({
@@ -1856,16 +1859,31 @@ if (url.search.length > 1) {
         return this.browserRequire("devtools/client/shared/vendor/react");
       },
       get ReactDOM() {
         return this.browserRequire("devtools/client/shared/vendor/react-dom");
       },
       isToolRegistered() {
         return false;
       },
+      currentToolId: "inspector",
+      getCurrentPanel() {
+        return "inspector";
+      },
+      get textboxContextMenuPopup() {
+        notImplemented();
+      },
+      getPanel: notImplemented,
+      openSplitConsole: notImplemented,
+      viewCssSourceInStyleEditor: notImplemented,
+      viewJsSourceInDebugger: notImplemented,
+      viewSource: notImplemented,
+      viewSourceInDebugger: notImplemented,
+      viewSourceInStyleEditor: notImplemented,
+
       // For attachThread:
       highlightTool() {},
       unhighlightTool() {},
       selectTool() {},
       raise() {},
       getNotificationBox() {}
     };