I didn't choose output to editor window. But, I did right-click on the search results and select open in editor window. I,m pretty sure they accomplish the same thing. The search results open in the editor window with all of the (regex) matches highlighted. Printing prints the text but not the background highlighting.
However, on second thought printing in text-only, non-html, I don't think the highlight can be printed. But, maybe it could be printed as bold-italics.
Jim