Hi, Tested on Helix Ultimate 2.0.1 and Firefox 91 and I was able to add break in Custom CSS.

Maybe try from diffrent browser, to be sure. You can also share access I can check.

So far only you had this issue.

The line break works for me neither in Edge nor in Firefox. I don't know how to share access ...

In "Hidden COntent" area put URL + Super User account (you can create a new for me)

I created the access ...

Thanks / Danke

In the meantime I discovered it's issue in last Helix update. I have this same problem in my sites. So we both have to wait for offcial Helix update. By now just add space between classes OR use custom.css file instead. Right now I cannot help more :(

I found many css problems with the 2.0.1. And I can not even change them...

As I said before ... please wait for next Helix Ultimate update 2.0.2. Should be soon, in next days. It should fix most of issues.

Thank you for your support...

By now focus on real content and add design using Page Builder etc.

Template can wait few days.