diff --git a/src/calibre/gui2/viewer/ui.py b/src/calibre/gui2/viewer/ui.py
index 178f2274d0..e585f47dde 100644
--- a/src/calibre/gui2/viewer/ui.py
+++ b/src/calibre/gui2/viewer/ui.py
@@ -85,18 +85,25 @@ class EbookViewer(MainWindow):
         self.bookmarks_widget.activated.connect(self.bookmark_activated)
         self.bookmarks_dock.setWidget(w)
 
-        self.inspector_dock = create_dock(_('Inspector'), 'inspector', Qt.RightDockWidgetArea)
+        self.inspector_dock = create_dock(
+            _('Inspector'), 'inspector', Qt.RightDockWidgetArea, areas=Qt.AllDockWidgetAreas)
+
         self.web_view = WebView(self)
         self.web_view.cfi_changed.connect(self.cfi_changed)
         self.web_view.reload_book.connect(self.reload_book)
         self.web_view.toggle_toc.connect(self.toggle_toc)
         self.web_view.toggle_bookmarks.connect(self.toggle_bookmarks)
+        self.web_view.toggle_inspector.connect(self.toggle_inspector)
         self.web_view.update_current_toc_nodes.connect(self.toc.update_current_toc_nodes)
         self.web_view.toggle_full_screen.connect(self.toggle_full_screen)
         self.web_view.ask_for_open.connect(self.ask_for_open, type=Qt.QueuedConnection)
         self.setCentralWidget(self.web_view)
         self.restore_state()
 
+    def toggle_inspector(self):
+        visible = self.inspector_dock.toggleViewAction().isChecked()
+        self.inspector_dock.setVisible(not visible)
+
     # IPC {{{
     def handle_commandline_arg(self, arg):
         if arg:
@@ -290,6 +297,7 @@ class EbookViewer(MainWindow):
             self.restoreGeometry(geom)
         if state:
             self.restoreState(state, self.MAIN_WINDOW_STATE_VERSION)
+            self.inspector_dock.setVisible(False)
 
     def closeEvent(self, ev):
         try:
diff --git a/src/calibre/gui2/viewer/web_view.py b/src/calibre/gui2/viewer/web_view.py
index 3c9066b5fb..5c63b346ae 100644
--- a/src/calibre/gui2/viewer/web_view.py
+++ b/src/calibre/gui2/viewer/web_view.py
@@ -187,6 +187,7 @@ class ViewerBridge(Bridge):
     reload_book = from_js()
     toggle_toc = from_js()
     toggle_bookmarks = from_js()
+    toggle_inspector = from_js()
     update_current_toc_nodes = from_js(object, object)
     toggle_full_screen = from_js()
     report_cfi = from_js(object, object)
@@ -305,6 +306,7 @@ class WebView(RestartingWebEngineView):
     reload_book = pyqtSignal()
     toggle_toc = pyqtSignal()
     toggle_bookmarks = pyqtSignal()
+    toggle_inspector = pyqtSignal()
     update_current_toc_nodes = pyqtSignal(object, object)
     toggle_full_screen = pyqtSignal()
     ask_for_open = pyqtSignal(object)
@@ -325,6 +327,7 @@ class WebView(RestartingWebEngineView):
         self.bridge.reload_book.connect(self.reload_book)
         self.bridge.toggle_toc.connect(self.toggle_toc)
         self.bridge.toggle_bookmarks.connect(self.toggle_bookmarks)
+        self.bridge.toggle_inspector.connect(self.toggle_inspector)
         self.bridge.update_current_toc_nodes.connect(self.update_current_toc_nodes)
         self.bridge.toggle_full_screen.connect(self.toggle_full_screen)
         self.bridge.ask_for_open.connect(self.ask_for_open)
@@ -337,7 +340,6 @@ class WebView(RestartingWebEngineView):
         if parent is not None:
             self.inspector = Inspector(parent.inspector_dock.toggleViewAction(), self)
             parent.inspector_dock.setWidget(self.inspector)
-            # QTimer.singleShot(300, lambda: (parent.inspector_dock.setVisible(True), parent.inspector_dock.setMinimumWidth(650)))
 
     def url_changed(self, url):
         if url.hasFragment():
diff --git a/src/pyj/read_book/overlay.pyj b/src/pyj/read_book/overlay.pyj
index 90a0f20a43..c32838f9e3 100644
--- a/src/pyj/read_book/overlay.pyj
+++ b/src/pyj/read_book/overlay.pyj
@@ -269,6 +269,12 @@ class MainOverlay:
         if full_screen_actions.length:
             actions_div.appendChild(E.ul(*full_screen_actions))
 
+        if runtime.is_standalone_viewer:
+            actions_div.appendChild(E.ul(
+                ac(_('Inspector'), _('Show the content inspector'),
+                   def(): self.overlay.hide(), ui_operations.toggle_inspector();, 'bug')
+            ))
+
         container.appendChild(set_css(E.div(class_=MAIN_OVERLAY_TS_CLASS,  # top section
             onclick=def (evt):evt.stopPropagation();,
 
diff --git a/src/pyj/viewer-main.pyj b/src/pyj/viewer-main.pyj
index 8b9a1a876b..17aab37162 100644
--- a/src/pyj/viewer-main.pyj
+++ b/src/pyj/viewer-main.pyj
@@ -255,6 +255,8 @@ if window is window.top:
         to_python.toggle_toc()
     ui_operations.toggle_bookmarks = def():
         to_python.toggle_bookmarks()
+    ui_operations.toggle_inspector = def():
+        to_python.toggle_inspector()
     ui_operations.update_current_toc_nodes = def(current_node_id, top_level_node_id):
         to_python.update_current_toc_nodes(current_node_id, top_level_node_id)
     ui_operations.toggle_full_screen = def():