It’s not very clear what was the modification made, as it seems to be in a missing image.
After a full, successful OIDC process, you are supposed to be redirected where you were when the auth started. To do that it remember and the store initial source URL to redirect to it and this depends a lot on a proper setup of the HTTP proxy you have in front of XWiki.
The following code can help understand exactly what information the HTTP proxy transmit about the source URL:
{{groovy wiki="false"}}
println 'HTTP header "forwarded": ' + xcontext.request.getHeader('forwarded')
println 'HTTP header "x-forwarded-host": ' + org.xwiki.container.servlet.HttpServletUtils.getFirstHeaderValue(xcontext.request, 'x-forwarded-host')
println 'Application server port: ' + xcontext.request.getServerPort()
println org.xwiki.container.servlet.HttpServletUtils.getSourceBaseURL(xcontext.request)
{{/groovy}}