Right clicking in overlays should act like Esc

src/pyj/read_book/overlay.pyj

@@ -471,8 +471,13 @@ class Overlay:
         self.view = view
         c = self.clear_container()
         c.addEventListener('click', self.container_clicked)
+        c.addEventListener('contextmenu', self.oncontextmenu, {'passive': False})
         self.panels = []
 
+    def oncontextmenu(self, evt):
+        evt.preventDefault()
+        self.handle_escape()
+
     def clear_container(self):
         c = self.container
         clear(c)