2 major problems.

1. it disable high contrast for all websites, not just the current tab.

2. When trying to revert back to High-Contrast, it doesn't work properly. You are forced to remove the extension to get High Contrast mode working again.

Not working for firefox 139. Sets to "customized" instead of automatic, not respecting browser's original configuration. Seems to be out of maintenance so I have to change to 1 star.

Useless

Somehow, this extension degraded contrast on multiple websites when the high contrast switch was turned OFF.
See https://daverupert.com/about/ for example