Whilst I'm still using uMatrix (and uBlock Origin), I still like it even thought it is no longer developed, it still serves a purpose.
Though it is nice to have more options, that are still being developed, AntiBrowserSpy, name sucks, I guess someone has BrowserAntiSpy. But Firefox also has many AntiSpy functions built in.
Also see
https://alternativeto.net/software/antibrowserspy/EDIT:
I did a search for ore information on this and there are many hacks for the Pro version of this - so it makes me wonder:
1. Just how good the free version would be.
2. People cracking it, some might go down that route only to find an unwelcome surprise.