I honestly didn't notice any difference in performance when Firefox Android Beta was switched to the new codebase a couple of weeks ago. Not saying it's not there, just that I couldn't tell.

I have trouble getting used to the new UX.

I keep hitting the address bar to open a site from my top sites in the current tab. That used to work, now it just opens the search interface. Instead you have to hit the -- much smaller -- tab overview button to open a top site in a new tab. Which means I end up having to manually close old tabs all the time now, something I don't remember doing. (To be fair, Chrome works the same way.)

I don't know how I'm supposed to use the new Collections feature. It's extremely prominent in the UI, I assume everybody else must be finding it super useful?!

They broke the offline reading list? You used to be able to bookmark a page in Reader Mode and have it available even when there is no connection (subway, airplanes). Instead of promoting this really neat (and given that Reader Mode is still a thing, cheap) feature, I think they just got rid of it. I had like a dozen of long articles in that list I still wanted to read (I think the bookmarks are still there). Hopefully they'll restore it before it transitions from Beta to Release, but who knows.

> the offline reading list

I've wanted a feature like this for years but I had no idea it already existed! Thank you for this info. And yes, please don't break it, Mozilla.

It is (used to be) somehow very well hidden and easy to reach, both at the same time.

yes I use and I totally agree that the preview version is much faster compare to the old firefox.