Search on Tag suggestions: how to make broader?

[CawlinTeffid]

This feature is strangely missing (or broken). There is a feature request (you can upvote it by pressing the heart or commenting with new info).

Tag and link auto-complete in search

I am routinely inputting tags, filenames and links into search. Auto-complete would be really helpful. As a side note, I am using search to filter backlinks and would like to see some convergence of these features.