I have the same problem within lists.

Is there still no way of a permanent fix? I have been using GIMP with forced gamma settings for a while and even reuploaded lots of my older images for this reason. But even that didn't work with some of my recent uploads, e.g. https://commons.wikimedia.org/wiki/File:Andr%C3%A9_Campra_-_Idom%C3%A9n%C3%A9e_-_title_page_of_the_score_-_Paris_1712.png - the jpg version of that image looks much better in the overview: https://commons.wikimedia.org/wiki/Category:Idom%C3%A9n%C3%A9e .