Request: Add notice with switch back link to Access Denied page in MultiSite

[MadtownLems]

When a Network Administrator switches to another user and tries to visit the dashboard of a subsite they don't have access to, they get a screen that talks about how they have no privileges on the site, and a list of the sites they DO have access to. This would be a great screen to output the message about how the user is currently switched to a non-network admin, with a link to switch back.

[johnbillion]

Thanks for the suggestion. I seem to remember that there are no useful hooks on that error screen, but I will take a look.

[MadtownLems]

Perhaps admin_page_access_denied could work?