Add setting to disable redirect file browser launch

jupyter_server/serverapp.py

@@ -879,6 +879,22 @@ def _default_allow_remote(self):
         else:
             return not addr.is_loopback
 
+    use_redirect_file = Bool(True, config=True,
+        help="""Disable launching browser by redirect file
+     For versions of notebook > 5.7.2, a security feature measure was added that
+     prevented the authentication token used to launch the browser from being visible.
+     This feature makes it difficult for other users on a multi-user system from
+     running code in your Jupyter session as you.
+     However, some environments (like Windows Subsystem for Linux (WSL) and Chromebooks),
+     launching a browser using a redirect file can lead the browser failing to load.
+     This is because of the difference in file structures/paths between the runtime and
+     the browser.
+
+     Disabling this setting to False will disable this behavior, allowing the browser
+     to launch by using a URL and visible token (as before).
+     """
+    )
+
     local_hostnames = List(Unicode(), ['localhost'], config=True,
        help="""Hostnames to allow as local when allow_remote_access is False.
 
@@ -1761,6 +1777,12 @@ def launch_browser(self):
         if not browser:
             return
 
+        if not self.use_redirect_file:
+            uri = self.default_url[len(self.base_url):]
+
+            if self.token:
+                uri = url_concat(uri, {'token': self.token})
+
         if self.file_to_run:
             if not os.path.exists(self.file_to_run):
                 self.log.critical(_("%s does not exist") % self.file_to_run)
@@ -1776,9 +1798,12 @@ def launch_browser(self):
         else:
             open_file = self.browser_open_file
 
-        b = lambda: browser.open(
-            urljoin('file:', pathname2url(open_file)),
-            new=self.webbrowser_open_new)
+        if self.use_redirect_file:
+            assembled_url = urljoin('file:', pathname2url(open_file))
+        else:
+            assembled_url = url_path_join(self.connection_url, uri)
+
+        b = lambda: browser.open(assembled_url, new=self.webbrowser_open_new)
         threading.Thread(target=b).start()
 
     def start_app(self):