Hi, I am using Special:RandomInCategory ( https://www.mediawiki.org/wiki/Help:RandomInCategory ) for some of the categories on Commons of images which I uploaded, bookmarked in my browser. E.g. https://commons.wikimedia.org/wiki/Special:RandomInCategory/Files_by_DerHexer/Internationales_Deutsches_Turnfest_Berlin_2017 , even more obvious in smaller categories like https://commons.wikimedia.org/wiki/Special:RandomInCategory/Elisabeth_Seitz_at_Internationales_Deutsches_Turnfest_Berlin_2017 .
Unlike expected, I do not get random images but some very often, sometimes even in the similar order when I click the bookmark, sometimes it opens only subcategories but not files. How can this happen? The function is very helpful and I would very much appreciate to promote this onwiki but this broken I am a bit hesitant.
Thanks for fixing in advance!