MHTML files not extracting

Although on the website for Universal Extractor keeps saying it supports MHTML files for extraction, there is a major problem with it. Most browsers that save in that format, save with the MHTML extension and not MHT, which is what Internet Explorer saves as.  So, what strikes me, is how can it say Universal Extractor and even ExtractMHT support MHTML files, when it won't even recognize the MHTML being used as an extension.  Even the Fork in the road, hasn't fix that problem. I would think people as smart as to make such a program would be as smart to realize that browsers save MHT and MHTML pages and both would be recognized and that Windows has both extensions in the registry.  Sure, I can change the MHTML to MHT, but who wants to change several hundred  file extension names?   Is there a simple way to fix this problem without having to change every MHTML extension to MHT?  And I thought the earlier version of Universal Extractor had no problem with extraction of that, but maybe it was another/ better program I used in the past?  I guess I will just use the Plugin for 7zip to extract that.