Divider for track-adder.
Hide track-adder buttons when not needed.
(More substantial refactoring would probably be a good idea, though...)
Merge remote-tracking branch 'upstream/master'
Split session-storage code (performance).
Tier-sizing fixes.
Avoid using stale data when responses arrive out-of-order.
Separate "UI control" keypress handers out to a separate handler in browser-ui.
Merge remote-tracking branch 'upstream/master'
Morning dalliance merge