Release 16 doesn't work in Gnome Shell 3.28 (Ubuntu 18.04): GObject.registerClass() used with invalid base class (is PanelMenuButton)

[uusijani]

I'm using Ubuntu 18.04, which has Gnome Shell 3.28 (3.28.3+git20190124-0ubuntu18.04.1).

After I updated the extension to latest release (16), it fails to start. Gnome Shell reports this error:

Extension "[email protected]" had error: TypeError: GObject.registerClass() used with invalid base class (is PanelMenuButton)

Downgrading to release 14 makes it work again.

Ubuntu's appindicator extension has a similar issue from a while back, with pointers to an issue with the extensions website, but I'm unsure if this is related.

In any case, I decided to open this issue to at least document it. Feel free to close it if it's intentional (Gnome Shell 3.28 no longer supported), or otherwise not a bug with System Monitor.

[pasquale95]

I have the same problem

[elvetemedve]

Hi @uusijani @pasquale95,
I'm sorry, but Gnome Shell 3.32 introduced a change in the Javascript engine which seems to break backward compatibility. I don't have time and willpower to install multiple version of Gnome to check compatibility of all past versions. Also I don't want to maintain multiple version of the extension supporting multiple Gnome Shell versions.

What I can suggest you is to downgrade the extension to Version 14 (it can be downloaded from the Releases page as a ZIP file), extract the contents into the directory ~/.local/share/gnome-shell/extensions/[email protected]/ until you upgrade Gnome Shell to 3.32 or later.

[uusijani]

@elvetemedve It's cool, V14 is working just fine so I'll just postpone updating the extension until sometime in the future. Thanks!