Sometimes rust-analyzer stops working. It seems to be related to how many projects you have open. I wish there was like a ui that would allow me to disable it for some projects and enable it for others.
You can. Projects in VSCode are called "Workspaces".
Every time I install an extension, I first "Disable" it, which is global. Then I switch to the workspace that needs it and choose "Enable (Workspace)". That way you only have the extensions you need per project.
I only ever have 1 project open at a time then switch to which ever other project I need to (RLS had the same issues), vscode makes this easy to do with ctrl+r but I don’t know what IDE you’re using.