Let’s go through examples:
“He’s retarded” - that’s a slur, unless it’s ironic.
“That was retarded” - not a slur, cause it’s kinda taking a dig at an action, not a person.
“I’m retarded” - technically a slur but almost always used with a hint of irony, therefore usually not a slur.
That’s how I use the word with my friends. And I have autism, so technically 100 years ago I would have been the resident retard ;)
Unfortunately OP is right.
Here’s some alternatives that use the same base as Mozilla, and maybe they might pick up the shards soon: Waterfox, LibreWolf, Mullvad Browser
Considering Manifest V3 in Chromium and how the browser kit is forcing quite a few things on us there’s also a solid chance people will independently rework the chromium base into a new web browser toolkit soon, but we’ll have to see. Either way, next few years will undoubtedly bring a lot of change to the browser landscape.