QtWebEngine Locked at 60FPS Despite Detecting 144Hz Displays

To reproduce the issue, compile and install qtwebengine (version 6.6.1#1) using vcpkg:

vcpkg install qtwebengine[geolocation,proprietary-codecs,spellchecker,webchannel,default-features]:x64-windows --editable --x-buildtrees-root="C:\qt" 

After installation, compile and run the following code:

#include <QApplication>
#include <QWebEngineView>
int main(int argc, char *argv[])
{    
    QApplication app(argc, argv);
    QWebEngineView view;

    // Check the refresh rate
    view.setUrl(QUrl("https://vsynctester.com"));

     view.show();

    return app.exec();
} 

The test results show that the refresh rate of QtWebEngineView is capped at 60 FPS.

When I set the URL to chrome://gpu/, it shows that Chromium correctly detects my 144Hz monitor, but for some reason, it's still limiting the max refresh rate to 60. 

I've tried using `qputenv("QTWEBENGINE_CHROMIUM_FLAGS", "--ignore-gpu-blacklist --enable-gpu --vsync-interval=7 --max-gum-fps=144"); with no luck. 

Also, using `qputenv("QTWEBENGINE_CHROMIUM_FLAGS", "--disable-frame-rate-limit");` pushes the frames beyond 500, but it maxes out CPU resources.