[KevinH]

Not sure if it matters, on the Qt 6.6.2 + (or maybe even Qt 6.5.X+), they have moved to QtWebEngine defaulting to each platform's native technologies for graphics. On macOS this is now metal, and for Windows it is Direct3D.

It is also controlled by a new environment variable:

QSG_RHI_BACKEND

With possible values: vulkan, metal, opengl, d3d11, d3d12

Requests the specific RHI backend. By default the targeted graphics
API is chosen based on the platform, unless overridden by this variable or the equivalent C++ APls. The defaults are currently Direct3D 11 for Windows, Metal for macOS, OpenGL elsewhere.

So you might want to try setting the environment variable:

QSG_RHI_BACKEND="opengl"

just to see if that fixes your image issues as it would try the orignal opengl interface in place of the Direct11 one. Or visa-versa or maybe try "d3d11" or "d3d12".