I essentially have only been using ublock origin for years as the only extension I bother with, but recently I've felt I should be doing more, so had a look at things like privacy badger and ghostery… but I know firefox has tracking protection on by default, so do those extensions even do anything?
What extensions do use to avoid overlapping functionality?
uBlock Origin for ad blocking
Multi-Account Containers, Temporary Containers, and Containerise for isolating sites from one another
Decentraleyes for limiting CDN requests
Containers are the best.
I would say it is an unknown killler feature on FF.