Has it been considered to visually separate the 'Additional CSS Class' setting from the above Panel? By default, it could be mistaken as part of the previous panel.
Current:

Idea:

I'm happy to provide a pull request if needed.
Thanks!
There is closed PR which does something similar by grouping such settings. I can bring it back to life and update if we agree to introduce visual changes as proposed.
I would +1 bringing that back to life @gziolo and adding this in. It feels like a simple improvement but useful one. Thanks for noting this @DannyCooper.
It was supposed to be inside an "Advanced Settings" panel, together with "anchor" setting.
I opened #5952 to address it, which is based on #3475. It still misses some inline docs but I'd like to get feedback if the UI part looks as expected.
Most helpful comment
I would +1 bringing that back to life @gziolo and adding this in. It feels like a simple improvement but useful one. Thanks for noting this @DannyCooper.