User blog comment:Rappy 4187/Technical Update: March 10, 2015/@comment-4714517-20150311212001/@comment-452-20150312162718

I don't see what uploading has to do with it.

Special:WikiActivity still shows exactly 50 when I set "Number of edits to show by default" to 500.

That number applies to Special:RecentChanges, Special:Log, Special:Contributions and ?action=history (edit: and Special:WantedPages and probably all other "normal" maintenance pages. The reason Special:WikiActivity doesn't use this number is because Wikia invented it.)

Kuopiofi, does this happen on all wikis, or just certain wikis?