QtWebEngine (Windows 10 x64) does not enable oop rasterization even with flag

I have been wracking my brain a bit trying to get this to work..

No matter what I end up with 'out-of-process rasterization: disabled"

I have tried:

• QT 15.15.5, 15.15.4, 15.15.1, and 15.15.0 (did not bother with 2 or 3, because I think it's just a problem..)
• The flag: --enable-oop-rasterization (unsuccessful with command line or qputenv at beginning before I init the app)
• forcing angle and forcing d3d11 (successfully works but does not give me oop rasterization)

The flags I last used and also tried via qputenv (QTWEBENGINE_CHROMIUM_FLAGS):

--enable-rasterization --enable-oop-rasterization --ignore-gpu-blacklist ---disable-gpu-driver-bug-workarounds --enable-zero-copy --enable-gpu-rasterization

Any help would be greatly appreciated.  On Mac, it just works without workarounds or flags, the same app.