How to Cancel a 'Hung' Search in Blueprint Editor?

Sometimes when I search in Editor in a Blueprint, the search continues “forever”, with an orange progress bar that has stopped moving, eg for a half hour, until I finally manually kill the Editor from the OS.

Is there an Editor key to cancel a search?

On the hypothesis there’s something “too broad” about my search, is there a configuration option to limit a search to the current project?

Other tips or troubleshooting ideas?