Problem with pre HDRP project on painting terrain

I can create and add layers but can't paint. I can do anything else to the terrain but not painting.
On a newly created project there are no problems.
I tried creating new layers and new terrain as well without luck.
Any suggestions?

 

The solution is here:
https://forum.unity.com/threads/can-not-paint-textures-on-terrain.577243/

But it's no good since using different texture quality is part of quality management and I rely on that.
Is it going to be fixed?

 

Since HDRP is in preview, they barely started to poke around the terrain, you can guess.

 

Thanks, I feared they never would have fixed it.

 

I tried to modify the files myself adding more layers but Unity raised an exception about serialization version.
Is there a way to do that or do I have to wait for a new release?