**System Information**
Operating system: Windows-10-10.0.19042-SP0 64 Bits
Graphics card: NVIDIA GeForce GTX 1650 SUPER/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 472.12
**Blender Version**
Broken: version: 3.0.0, branch: master, commit date: 2021-12-02 18:35, hash: `rBf1cca3055776`
Worked: 2.93
**Short description of error**
There is no option to change NodeGroup background color (with alpha).
Also (if it's intended for 3.0, but imho it's a bad decision) BG color in ShaderEditor is different than in NodeGroup
**Exact steps for others to reproduce the error**
default "Blender Dark" theme
|in Shader Editor {F12689190}|in NodeGroup {F12689191}|
Also, alpha for Group Node color in 3.0.0 not working as in 2.93
|Blender 2.93 {F12689245}|Blender 3.0.0 {F12689246}
more visual example:
if we change "Themes - Node Editor - Theme Space - Window Background" green channel to 0.5
|in Shader Editor {F12689198}|in NodeGroup {F12689199}|
Also, alpha for Group Node color in 3.0.0 not working as in 2.93
|Blender 2.93 {F12689245}|Blender 3.0.0 {F12689246}