Theming issue in v13.0.1

Nextcloud version (eg, 12.0.2): 13.01.
Operating system and version (eg, Ubuntu 17.04): Debian 9 (stretch)
Apache or nginx version (eg, Apache 2.4.25): nginx/1.10.3
PHP version (eg, 7.1): 7.0.27

The issue you are facing: log in screen is not shown with own picture and logo.

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

Steps to replicate it:

  1. Uploading logo and picture

Link and slogan can be edited.

Any idea how to get this fixed?

Kind regards