Been an ongoing issue for a long, long time . . . using the search block often just sits and spins forever. Sometimes deleting my search string and trying it again eventually works, sometimes refreshing makes it work, and sometimes who knows what I do but it works. I can’t imagine I’m the only one who has this issue.
This is yet another reason that Blocks should be crafted using open web standards, easily extended, and open enough so we can help to make them better.