Safari 26.1 still not opening .webarchive files correctly

When I updated to Safari 26.0.1 as well as Sonoma 14.8.1 on my 2022 MacBook Air, a problem soon became apparent: I couldn't open saved .webarchive files correctly. Website access is fine, but when I load saved .webarchive files I get the path and name and occasionally a loading bar which never moves. The page is blank. I can load the files with a text program, (no corruption in the files). I have just updated again, now to Safari 26.1 and Sonoma 14.8.2 and yet the problem persists. I have no extensions to interfere with anything, and have no idea what to try next.