The "Preseved tags" input in Options > Tags has an autocomplete feature, suggesting tags.

But this does not work too well:

• Completion only triggers, if you don't have spaces after the comma. So writing "artist, t" will not trigger suggestions starting with "t", only "artist,t" does
• Once a completion has been selected it is entered into the edit field, but the user has to manually add the comma to enter another one. It would make sense to enter the comma for them so it is easy to enter multiple tags