Google messages app stuck in the login window and doesn't open , says " cannot login "

[ale5000-git]

Hi, this is the support for the installer only.

Your problem look like a problem of microG itself. It is probably already fixed here: https://github.com/microg/GmsCore/commit/ae2cc4d5d1e3950acc14a8be7f17a6bd3f530c4f

I suggest to wait the new version and retry.