Gnome extensions stay in the list after being removed
How to remove one or all Gnome-shell extension(s) completely
Open terminal: (from app menu or by pressing Ctrl+Alt+T)
Then type: sudo su - and type your password and press enter
then type this command:
cd /home/"your user account"/.local/share/gnome-shell/extensions/
then type this command to see all your installed extensions: ls
then type this command to remove each or extension you really want to remove it completely:
rm -r name-of-extention
for example : rm -r [email protected]/
and press : Alt+F2 then type “r” yes simple just one r
Ok it done.
You can check extensions.gnome.org to be sure about this.