Sometimes it appears the extension doesn't work, but... it does? in a different tab.

[ddurst]

I tried using this on a google search results page and could not get a response.

But then I noticed that the results were taking effect in another tab I had open where dev tools was also pulled up. So I searched for, say, div in tab G (google stuff) and got no response, but I go over to tab H (which happened to be Github) and that dev tools panel has executed the search for div (it does not display the query in the search bar there, but it does display the results in the panel AND shows it in the page overlay).