Even when idle top reports gnome-shell using 50%-95% CPU. I had this problem previously, which I solved by removing various extensions, but now it’s happening again and hindering my system’s usability.
Is there any way to see what is making gnome-shell so suddenly resource hungry?
Removing outdated/unmaintained extensions would be a start. You may create a new “test” user account and see if problem persists, that means it’s a package-level problem and needs dev attention.
if you installed extensions from various sources (AUR, gnome extension website, pamac, github/gitlab etc.) then, nah
How many extensions do you have? More the merrier messier.
All the installed extensions should be in 2 folders (at least on my system they are) and this command lists them all: ls -1 /usr/share/gnome-shell/extensions > allextentions && ls -1 ~/.local/share/gnome-shell/extensions >> allextentions and put them in a file allextentions for reference.
If you have firefox there is the options of installing the gnome -shell integration add-on and it will list the installed extensions and allows the option to manage the user space extentions