Bug UI Builder doesn't support linear color space (and UI toolkit too?)

Today I've noticed that somehow I don't use linear color space in my project. I've fixed that, solved many issues I had with lightning, but now I have a problem with UI. Most of it is broken.

The first thing I found while searching this issue was a piece of information about trying to implement an option to have UI rendered in a different color space than the rest of the game. That was exactly 2 years ago. What was the result of that research? I suppose that it's simply not possible or not going to land anytime soon. It's not even on the roadmap.


But now, there are a lot of problems with linear color space in the UI Toolkit making a simple switch absurdly difficult. For example, UI Builder doesn't support it at all.


Here is how my UI looks in linear color space (Game view):



Here is how my UI looks in gamma color space (Game view):



Here is how my UI looks in UI Builder while the linear color space is turned on (I've added a picture from the scene view as a background):


Now, How I'm supposed to quickly adapt anything when I have to switch between UI Builder and game view to see what I'm doing?


And that's not the worst part, I have something more dramatic. The font got somehow thick to the point of me getting a problem with reading the text.
Here's the comparison:



Icons got thicker too



I'm trying to find whether this is normal as the linear space changes blending. So far, I have only found posts from around 2015 about UI which don't apply sRGB. I wonder whether it's the same problem here. I can see all colors in the linear space looks unnatural, too bright, faded.

I'm using unity 2021.2.10

 

@SimonDufour any chance we might have a dedicated color space setting in the UI Panel Settings? I don't like the "use a render texture and blit it" solution

 

Is a linear-space UI builder on the roadmap at all?

 

High transparency gradients look horrible in linear color space, because of the banding:
This prevents UI Toolkit in combination with HDRP (which requires linear color space) from being production ready.