I see that other people have had this issue, and possibly have had it solved with an update. We however are still having the issue. We did not have the issue a few weeks ago, but do now. We added a new site from our multisite to domain mapping and now we see the "You have logged in successfully. You will be redirected to desired page during next 5 seconds" screen.
I'm wondering why this is happening now, and it wasn't before. We have tried every possible combination of options on the DMapping settings (domain mapping schemas) as well as trying to force HTTPS, HTTP, & None on all of the domains. This happens on all of the mapped domains on our multisite – again, this wasn't happening before we added the latest site a few weeks ago.
I'd like to not have it, but if we must I want to know about customization. We have added our own logo to replace the WordPress logo, but this will get overwritten with any updates. Is there a way to hold onto the customization? (We have modified this file: plugins->domain-mapping->classes->Domainmap->Module->Cdsso.php)