There is a an excellent tutorial on Medium.com called Mediawiki and Azure AD Single Sign On with step by step instructions how to set SSO for MediaWiki with Azure, but it’s a bit outdated.
One note is that the Reply URLs is now called “Redirect URIs” in Azure, in the Authentication tab. We also used both of these URI’s there:
as it wasn’t clear which one was working, but with both, it anyhow works. 🙂
Beyond that, the code for the username provided did not work for us, so we left the code and used this for the settings:
$wgSimpleSAMLphp_UsernameAttribute = 'http://schemas.xmlsoap.org/ws/2005/05/identity/claims/surname';
Aside from that, the basic directions there work. If you have any questions or need help, just contact us.