Upload custom Background image in Theming App don´t work

ℹ️ Support
1

i don´t know why but it´s not working for me. (missing Styles.css)

https://github.com/nextcloud/server/issues/315

2

Dumb question:
Did you clear your memcache (Redis)
Did you clear the Browsercache?

3

redis not but browsercache

4

Could be worth restarting nginx/Apache, clearing your browser cache and see if that changes anything.