It has the most powerful search of any email client I've used. That was one of the reasons I switched. What issues have you had?

Search works really well for me. Definitely reveals a less aesthetic side of Thunderbird but it works!

A works to archive messages btw, I'm not sure about a shortcut for labels though.

What a weird thing to read. I open my work's email in thunderbird because the search is so good. Outlook is really slow when searching for something and so so tedious.

In all fairness, my usage is still minimal at this point. I’ve only searched a couple of times, but the thing I needed popped right up. Maybe my experience will change over time.