`dom.text_fragments.enabled` to remove "Copy link to highlight" on right-click. Yes, it can be useful, but I never use it and the very rare occasion of needing to use it when opening a page, I can just search it myself.
`privacy.query_stripping.strip_on_share.enabled` to remove "Copy clean link". I would rather it just did that clean link thing automatically, but I don't actually care about clean links -- it's just annoying having two "copy link" next to each other (especially with one which is greyed out 99% of the time!)
It strips query params used for tracking. Has it never bothered you when you click share on Instagram or YouTube and it inserts a unique-to-you "share ID" in the URL? I was burned by this once, now every time I copy a share URL from a social media platform I first paste it into my text editor and remove all of the privacy invasive tracking cruft.
As an aside I think it's only matter of time before this is done without query params and instead each share link is generated just for you.
The latter, especially, seems helpful.