mobile firefox misses tab hiding too, which is needed for tab grouping addons, so I doubt the feature will come there in the foreseeable future
That's neither rooted in reality nor fact. I've seen the spec and mockups for mobile. Is there any particular reason you're spreading this disinformation?
the source of my so called "disinformation" is the browser compatibility table in the Mozilla Developer Network article on the tab hiding API of WebExtensions
now its my turn. why are you spreading the disinformation that firefox mobile supports tab hiding and tab grouping addons?
where can we read the spec?
where can we see the mockups?
which tab grouping extension is working on firefox mobile?
This has nothing to do with extensions. Perhaps read the linked bug and get up to speed with what this is about, native tab groups in Firefox.
Firefox
A place to discuss the news and latest developments on the open-source browser Firefox