uMatrix looks like the kind of tool I was thinking of, thanks. I just wish I didn't have to give an addon permission to: Access your data for all websites Cle

uMatrix looks like the kind of tool I was thinking of, thanks. I just wish I didn't have to give an addon permission to: Access your data for all websites Clear recent browsing history, cookies, and related data Read and modify privacy settings Access browser tabs Access browser activity during navigation But that's just the very broken permissions model that addons currently have so thank you.