I left a comment for other users on the Gnome extensions site for this one, but until there is a release of #148 you have to manually add support for gnome 42:
vi .local/share/gnome-shell/extensions/netspeed@hedayaty.gmail.com/metadata.json
- add
, 42 to the array of supported versions
- logout/login (so the metadata is reloaded, that happens during your login)
- you may need to re-enable it using the "extensions" applet (which itself may have problems with Wayland according to it's reviews, I dunno I use old school X still...)
Hope this helps others, thanks for the applet @hedayaty :-)