Critical libs are from R3dFox project. And browser\omni.ja\modules, too.
129 x64 version works fine on Win 7. MAYBE it could run on Vista, too.
129 x86 version have huge problem to start with Firefox.exe on Win 7, even with VxKex and additional libs. So, r3dfox.exe is used for now.
Works on Win 8.1 at least.
It is recommended to use 129 x64 version or 128 x86 version.
BONUS:
LibreWolf 129.0.2 x64
Zen browser 1.0.0-alpha29/alpha33/alpha39 x64 (new project based on FF 129 https://github.com/zen-browser/desktop ) works with VxKex 1.1.1+.
Floorp portable 11.17.7/11.18.1 x64 Win 8+, 11.17.7/11.18.1 x86 works on Win 7 with VxKex!!!
Revert this patch https://github.com/Floorp-Projects/Floorp/commit/78eb92d83f9b00a40838257984acffc4c6590344.patch
Ghostery portable 2024.8.1 x64 (new project based on FF 129) - Enable VxKex 1.1.1+ for Gostery.exe or use it on Win 8,1.