Background color or image not visible in frontend

I've lowered the php to 8.1.17 but still the same. I see the changes in the working area, but the background stays white in the frontend.

I know where it goes wrong. I can give a row a background color or a background image. It works (i see it in the frontend), but when i type a title in the title section of the row, the backgroundcolor or image isn't visible in the frontend or disappears...

I'm not going to put that site online. I use page builder 3.8 for my online site. I just wanted to try version 4 and see the possibilities. But there is a bug(s) in version 4. When you give a row a background color, it also works in the frontend, but when you give that row a title and save it, the css for the background disappears and becomes the background white again. The same thing happens with a background image. I've tried it on another offline site (xampp) and i have the same result. Try it out for yourself.

Or it's a problem with xampp

I have pages which have lost background color as well. I should say those pages never inherited background color from the template. Why is this happening ? Ho can we fix this ? What is wrong with interaction between Helix and SPPB ???

I think [https://www.joomshaper.com/forum/question/22861] is about the same problem