I use the option to sync my bookmarks to my Mozilla account and I use the same bookmarks on the Desktop and Android version of Firefox.
What bothers me that when I want to open a bookmark on the Android version of Firefox I have to go through multiple folders to access my Desktop bookmarks (tap "Bookmarks" -> Desktop bookmarks -> Bookmarks Toolbar -> bookmark I'm looking for) every single time I want to open a bookmark.
I think it would be great for Firefox to "remember/save" the folder you opened the last bookmark from and the next time you tap "Bookmarks" in the menu, the folder you last were in opens. Of course, when you close Firefox and you open it again and tap "Bookmarks" you would be brought back to the menu it usually opens when you do that. What I want to say is that Firefox "remembers/saves" the folder you last opened a bookmark per session and resets upon closing the app.
I know that this is a minor and petty feature, but I would love for it to be implemented in some kind of way.