Nextcloud Android app blank/white screen after loggin in

Nextcloud version (eg, 18.0.2): 18.0.6.0

I use the LinuxServer(dot)io LetsEncrypt Docker to reverse proxy the LinuxServer(dot)io Nextcloud Docker, so:
Operating system and version (eg, Ubuntu 20.04): Alpine x86/x64
Apache or nginx version (eg, Apache 2.4.25): Nginx 1.18
PHP version (eg, 7.1): php7 packages from Alpine

The issue you are facing:

I recently purchased a new phone, and now I need to login to my selfhosted Nextcloud again through the Android app.
In between the last time I had to login on the Android app, I have upgraded my docker from v16 or something to v18.06.

While everything is working smoothly and the security checks are all cleared, I have an issue logging in to my Nextcloud server through the Android app.

I supply the domain name on which my Nextcloud is accessible, so far so good, it is loading the custom background and logo, great!
Now I login, but shortly after doing so, the screen turns blank. (white) And nothing happens, there is no network activity either.

Nginx reverse proxy file:
https://cryptpad.fr/pad/#/2/pad/view/rsZ3c9obOe18J1dfjLSSXJ5VgipuM16o2A8SxfDxWj8/embed/

Is this the first time you’ve seen this error? (Y/N): Y

Steps to replicate it:

  1. Have a what seems to be a properly functioning Nextcloud setup, with my configs
  2. Clean install a Nexcloud app on a clean Android phone
  3. Try to login…

The output of your Nextcloud log in Admin > Logging:

I emptied it before trying to log in again... it stays empty, even with my config debug levels...
I tried logging in a dozen times, but no log.

The output of your config.php file in /path/to/nextcloud (make sure you remove any identifiable information!):
https://cryptpad.fr/pad/#/2/pad/view/C7E3UBHy4d1yqbi6d6ZREW87zX60mfwkdhTE+JinBvk/embed/

The output of your Apache/nginx/system log in /var/log/____:
Access.log:
https://cryptpad.fr/pad/#/2/pad/view/Qtljj5frT89kdVjSwwqyrcQU+SEk1LxkjUYW27KlxnA/embed/

Error.log:
https://cryptpad.fr/pad/#/2/pad/view/Gpu9-aScoOaktgEB8+T0U17S9iUnlUPG1elwy+ocIr0/embed/

There seems to be something up with the password in the Error.log…?
My password is 16-20 characters long with special characters and upper, lowercase characters. (randomly generated)

Thanks in advance for any help or insights!

Same problem. Anyone got an idea?

Delete and reinstall?