For me nothing was enabled by default, thank goodness.

no, its part of the 100% optional experimental features section of Firefox (now called Labs). Its always been there (since its existed in Firefox Nightly for years), you just had to enable the menu panel option with a configuration setting, but now it (the menu panel) is shown by default. It should be noted, with very few exceptions, none of the items in this menu were ever enabled by default, unless they were to test turning off features for suneset reasons or spec changes (i.e., SameSite cookie permission attributes).

Yes, but it’s specially in the new update for Librewolf

Correct

New 130.0-3 update, it’s brand new. Make sure you update to the latest version (or don’t)

Definitely some Firefox crap, I doubt the Librewolf devs would want this in there

It’s in version 130.0-3, brand new