Fenix: Consider not displaying separators in the bookmarks UI

[grigoryk]

[grigoryk]

In https://github.com/mozilla-mobile/fenix/pull/15213 folders are moved to the top of the bookmarks UI, but this creates fun edge cases such as https://github.com/mozilla-mobile/fenix/issues/2792#issuecomment-511971100

I think we only have two options here:

• do nothing and leave it as-is
• _not_ display separators at all to avoid this. Not good for users who care bookmark about separators on mobile, if these exist. I don't think Fennec displayed bookmark separators, but it'll be nice to double check this. We don't allow editing these, anyway...

Pretty sure just doing the latter will be fine, this issue is just to force me to think about this again not on 10pm on Friday night.

[grigoryk]

Another option is to keep separators and just make them work well (e.g. allowing deleting, moving and maybe even creating them). I'm leaning toward that... Edge case described above seems pretty harmless, and something users can probably understand/expect to happen.

[CenCerberon]

You should also consider syncing between desktop and mobile.
The use of separators on the desktop is very important to me. On the mobile, I could live without separators.
Are these edited separators then synchronized back to the desktop?
It would be a shame if you either have fun edge cases on the mobile or on the desktop.