I don't think it's fair to call not knowing that a feature was removed from a discontinued app "making stuff up."

I was clearly wrong, though it is easy to change your user agent it's unlikely that many Firefox users have done it.

You're right, I misunderstood your comment. I interpreted what you said as in, you can get this feature via either Matrix or uBlock. I see now you meant one of those has the feature and you weren't sure which one had it. Sorry about that. In my defense I think it can be read both ways.

I'd add there is a large gap in usage between uBlock and Matrix. uBlock has over 10 million users whereas Matrix is somewhere over 100,000.