Unable to upload 10MB attachement to Xwiki, prompting HTTP 413 Error

I’m running XWiki 11.10 on Tomcat with a Postgres-DB and unable to upload a 10 MB attachment to the XWiki but getting a HTTP 413 Error. I have tried extending the size limit /xwiki/bin/edit/XWiki/XWikiPreferences?editor=object to 3355443200 3.2GB but issue still persists, please advise.

By default XWiki stores attachments to the file system and the default limit is 100GB so I doubt that your problem is with the size limit unless you had modified it or you have upgraded from an old version of XWiki where this size was set to a low value.

See https://www.xwiki.org/xwiki/bin/view/Documentation/AdminGuide/Attachments

Could you confirm you’re using FS-based attachments?