transparent window faintly tints the background

[chozabu]

Tested versions

-reproducible in v4.5.beta3.mono.official [4d1f26e]
-reproducible in 4.3

System information

windows 11 - v4.5.beta3.mono.official [4d1f26e] - compatibility rendering - geforce 4090 laptop - multiple monitors

Issue description

Enabling window transparency ( checking the three transparent window options in settings ) works, but the transparent window tints whatever is behind it - effectively being faintly white.

The issue is inconsistent - sometimes the window is more opaque/transparent than other times - unsure as to cause for changes.

Setting clear color to (0,0,0,0) does not fix the issue

NVIDIA_Overlay_FxEHRfQfZo.mp4

Steps to reproduce

Create a new project, in settings search for transparent, tick all three required options for making a window transparent, run project.

Minimal reproduction project (MRP)

minimal-transparant-window.zip

[Calinou]

Do you have HDR enabled in the Windows settings? If so, try disabling it.

[chozabu]

Do you have HDR enabled in the Windows settings? If so, try disabling it.

HDR is not enabled in windows settings

(edit: enabling HDR, or disabling it again does not seem to make a difference to the issue)

[bruvzg]

Is it doing this if the window is set to borderless?

[chozabu]

Is it doing this if the window is set to borderless?

Setting the window to borderless does fix the issue but it didn't yesterday I first noticed the issue in a project which uses a borderless window. That and other projects with borderless windows no longer have this transparency issue.

Since reporting this bug, I have at least:
-updated to latest nvidia drivers
-turned (nvidia settings) digital vibrance down to 50%, and back up to 60%
-changed "performance options" to best performance, and back to best appearance (in system properties/advanced system settings)
-turned nvidia overlay off, and back on

Though I don't know which if any of these actions have made a difference, as I've only been testing on the project with a window that has a border.

I'll test with both a regular and borderless window from now on