The issue has been closed
How hard would it be to have the ability to disable any new options by default? There have been a number of changes recently that I don't care for, and I find myself struggling to find the name of the preference that was added.

Like you can’t disable new features in any websites, we shouldn’t do it here either. We don’t actually guarantee that features don’t depend on each other and some CSS is injected anyway.
Also what’s “new”? Would an improved feature be considered new? What if infinite-scroll
starts working on new pages?
Not worth the effort
posted by fregante over 5 years ago
I like the way how Tab Session Manager highlights new settings:

Very easy to author if the new setting is relevant for me.
posted by jerone about 5 years ago
@jerone not a terrible idea, but then the extension needs to keep track of new features locally (I don't want to have to remember to un-mark a feature as new nor have to add a dateAdded
date right before merging a PR)
PR welcome if the code to add that isn't too long :)
posted by fregante about 5 years ago