I fixed this issue by modifying my config.php as per a post on github.
I had a similar issue regarding the redirect , mine was related to url overwrite protocol option that should be set in
config/config.php.
In previous version this was not necessary but apparently since 15.0.2 it is.
So I had to go from (config.php)
{...} 'overwrite.cli.url' => 'https://domain.lu', {...}
to
{...} 'overwrite.cli.url' => 'https://domain.lu', 'overwritehost' => 'domain.lu', 'overwriteprotocol' => 'https', {...}
This did the trick for me…
For information I’m running nextcloud docker behind a reverse proxy (which also handles ssl).
I have found the solution on this thread : nextcloud/server/13713Hope it helps !
Logout still takes ages, but I believe that is being addressed in v18.