I apologize for being unclear. Let me try to clarify:

Having the same problem with Chrome 75.0.3770.100.

Apologies, this is my first request of this nature. Thank you.

Sorry, should have specified. En.Wikipedia. The room has 30 computers so that would likely be the maximum number of accounts.

I'm in, thank you!

In T170097#3428888, @DESiegel wrote:

I was able to log in and apply through the staging url , although the resulting profile lists my date of joining Wikipedia as 2010, which is several years late, and lists my group memberships as autoconfirmed, ignoring my admin group membership, and several others (online course volunteer for example). i didn't try the basic address.

I'm able to log into https://twlight-staging.wmflabs.org/ now! Still unable to log into https://wikipedialibrary.wmflabs.org/ though.

In T170097#3424461, @jsn.sherman wrote:

I flipped on some much more detailed logging for the authentication process in staging. If impacted users attempt to login there again, I'll be able to examine all of the data coming back from oauth and our api calls.

In T170097#3423565, @jsn.sherman wrote:

Hmm, having spent some time chasing this down, I think we're not getting as much back from oauth on these accounts. I've worked up some changes in the staging environment and was hoping that one of our affected users could try logging in there. Basically, I've switched out some of our references to the oauth return data to api calls.