The Collections process is very cumbersome, and I've found that the Collections pages are a bit buggy - for instance, the adding-to-a-collection part uses a separate search bar that doesn't even find a large swath of store extensions for some reason.
It works, but is a decidedly poor experience.
On android, you can keep a copy of Firefox 68.1, ESR, ready to run. If you run in desktop mode, you can use all your favorite old plugins. Then use a Nightly version, for daily browsing, if you are worried about up to date security and features.
(ESR= extended service release.)
That's what I do, but even this ESR isn't supported anymore.
Why do you need to create a collection? I was happy when all extensions was the only collection. And this has been in Nightly for about a year.. when is it coming to stable? (those questions aren't really questions, it just looks like Mozilla is trying to make extensions go away)
I agree. However, as an extension author, I was happy to hear that the work I put into making it compatible with Android didn't go to waste after all. Still better than nothing.