Your thoughts have been shared by many others and is a proposed addition to the new forum software, but that has delayed for so long that I wouldn't keep my fingers crossed.
Me neither.
But I don't think it works anymore, does it? From that thread:
Not sure if op is still active, possible to make chrome extension as well? Because many mobile browsers support chrome extensions (kiwi, yandex) while not Firefox ones.
Last seen July 2018, not a good sign.
I happened to see someone posting about this mobile addon but noted the OP has been inactive for over a year.
So chances are pretty slim if he would update Firefox's, let alone create one for Chrome.
Do you use it?
On the other hand, it doesn't bother me much either, as I'm used to it. A mobile version would be better, but it's always worse than PC.