Hello,
I am trying to change the maximum file upload size through XWikiPreferences as described by Attachments
Whenever I’m hitting save on the XWikiPreferences page however, I run into an authorization error: 
I’m an admin on our xwiki, and have had other admins try as well. A non-admin is not able to reach this page.
Any ideas on what might cause this?
No idea.
Are you forbidding cookies in your browser by any chance?
Maybe try with the zip demo version and verify if you can reproduce? If you can reproduce with it, then we’ll also be able to do that and fix any problem. It may also give you some idea about how your wiki setup is different from the default.
Hi @vmassol,
I spun up a docker image of the default xwiki 12.5.1 and was able to make modifications on the preferences page without any problem.
One thing that is different from that is that we are using the OIDC plugin in our setup. I have tried to bypass that by creating a new user (with admin privileges) on our xwiki and logging in with ?oidc.skipped=true. This however still gives the same end result of being able to get on the page and modify items, but when saving running into the authorization error.
After further investigation, it turns out our Akamai WAF was blocking the modification on the XWikiPreferences object editor page.