Different rendering between windowed and fullscreen modes

[darkx1us]

Description of the bug
Fullscreen mode is much brighter and less contrast than windowed(incl. border). Windowed mode looks much more closer to original hl2 gamma.

To Reproduce
Steps to reproduce the behavior:

1. Turn fullscreen render mode

Expected behavior
Make fullscreen rendering looks like windowed

Screenshots

Desktop:

• OS: Windows 11
• VS 2026
• cmake version 3.31.6-msvc6
• HL2 x64

[darkx1us]

Solved. Switch off mat_monitorgamma_tv_enabled to 0
To do: needs GUI for toggling