Overflow editor icon bar icons into hamburger

[david-a-wheeler]

The editor icon bar icons already overflow into 2 lines on Firefox on my Samsung Android phone. The undo/redo icon will make even more phones go multi-line. Smartphones are widely available, but they also have limited screen space.

I recommend "overflowing" icons into the hamburger; this is done in other applications. Then any icons that can't fit quietly move into the hamburger, so all capabilities are still available without using up limited screenspace.