Further refactor/testing should be done on the back-button handler, because now when I visit https://www.mediawiki.org/wiki/Multimedia/About_Media_Viewer and click on an image that isn't the first, then use alt+left-arrow to go back, it redirects me (?) to the same image. I don't know why.
Reported by someone on Mac OS X and Chrome, with cmd+left-arrow instead, and instead it loaded the previous image for her. Browser testing may be in line here too.
Version: unspecified
Severity: normal