I have this login issue on Chrome:
Nextcloud version : 21.0.2
Operating system and version of client: Windows 8.1
Operating system and version of server: don’t know → docker
Apache or nginx version (eg, Apache 2.4.25): The one that comes with the current docker image
PHP version (eg, 7.4):
Attempt to login to Nextcloud21.0.2 from Chrome (91) on Windows just directly reloads the login page. Happens just the same for any user.
However, if I use the Chrome incognito mode I can log in ok. Also works on Firefox in normal mode. And all other clients (Andriod) all works ok.
Nextcloud in docker container running on Terramaster NAS.
There is no proxy, so I use the http access only as I use it only on internal network.
Previously I had NextcloudPI running with Nextcloud 17 and no issues. Problems started after upgrading to NC19. Then I migrated from NCP to NC (still all docker images).