By default, the Mailspring Sidebar shows a lot of items that I don’t really use in my email workflow (e.g. starred, reminders, snoozed). Since the upper icons take up a lot of screen real estate, it would be great if the user could configure which items will be placed there. Right now, a lot of items that I never use push down the ones I really depend on (my folders mainly), which wastes a lot of space.
The best solution would be to make this configurable from within the Mailspring settings.
I tried to do this myself through theming or a plugin, but could not really succeed. An alternative, much more easy to implement fix would be to give every item in the sidebar a distinct ID, so that one could e.g. simply disable those items through theming. Right now those elements are just divs without a classname or ID.