Extension crashes with TypeError: this._watchDog is null on Ubuntu 24.04

[prowlett]

In Ubuntu 24.04, I installed GNOME Shell integration extension on Firefox and chrome-gnome-shell through apt, then installed AppIndicator and KStatusNotifierItem Support.

It has appeared under User Extensions in the Extensions app with a toggle turned on.

After a few minutes of operation, I noticed the toggle has changed - it's still on, but greyed out and there is a cross in a circle next to the toggle and when I click this it says "An error has occurred in this extension" with the details TypeError: this._watchDog is null.

[AsciiWolf]

Is there any reason why are you not using the system "AppIndicator and KStatusNotifierItem Support" (gnome-shell-extension-appindicator) extension that should be enabled out-of-box on Ubuntu?

[prowlett]

@AsciiWolf Thank you for replying. I'm sorry, but I don't understand what you are asking me. Can you explain what you mean?

[AsciiWolf]

Sure. If you install a standard Ubuntu 24.04 desktop image, there is no need to manually install the AppIndicator extension because it is already installed as a part of the base (Ubuntu customized GNOME) system.

If you use some non-standard configuration (with stock GNOME etc.), you should install the gnome-shell-extension-appindicator package using Apt.

[prowlett]

Oh okay, thanks for explaining. I installed this in response to a suggestion to fix a problem I was having (a system tray app icon which didn't produce its menu when clicked. (I installed the extension and it didn't seem to want to turn on, but the menu now appears so I'm confused about what I did.) Anyway, because it gave weird results I thought I'd report it - happy for you to close the issue if it isn't needed (which it sounds like is the case).

[shock99er]

Hi there!, I'm esperiencing the same issue as prowlett ... The dropbox menu did not appear after clicking on the tray icon, which looks like the issue you have been experiencing. prowlett : did you manage to have it working without this AppIndicator and KStatusNotifierItem Support gnome extension? Otherwise, since it was a brand new installation of Ubuntu 24.04, I really cannot understand how it was suppose to work... Thanks for your feedback! Shocker

[rag2]

Also on Ubuntu 24.04, running GNOME Classic, experiencing the same issue. I think that the syndrome is triggered by a notification.

[timrichardson]

I have this too.

v60

"Stack trace" from journalctl is:

Aug 29 01:37:40 black gnome-shell[166786]: Extension [email protected]: TypeError: this._watchDog is null

                                   Stack trace:
                                     ...
                                     addNotification@resource:///org/gnome/shell/ui/messageTray.js:580:14
                                     processNotification@resource:///org/gnome/shell/ui/notificationDaemon.js:366:14
                                     NotifyAsync@resource:///org/gnome/shell/ui/notificationDaemon.js:263:16
                                     ...

the logs indicate that in the same second, a background backup app running a cron job sent a notification upon completion.