This is something that can ship pre-Proton, so it can happen immediately, and doesn't need to be behind a pref.
This is mainly removal, so should be reasonably straight-forward (he said, tempting fate).
For now, Library should be as follows:
View Pocket List
What we need to do:
- Remove the "Synced Tabs" and "Recent Highlights" sections.
- Have the "Downloads" button open up the Downloads section in the Library window. That can be done by using the
DownloadsPanel.showDownloadsHistory(); function, like this. This also means removing the "subviewbutton-nav" class from the item to get rid of the ">".
- With the Downloads subview no longer accessible, we can fully remove it. That means getting rid of DownloadsSubview.jsm, this chunk of markup, and any tests that exercise the Downloads subview. Also a good opportunity to cull any strings that aren't being used anymore with that subview gone.
Naturally, any tests that rely on the old structure or old behaviours will need to be modified as well.