How to enable "glass" effect in Windows 11 (DWM) ?!

[LoRd_MuldeR]

Does anybody know how to get a proper "glass" effect on Windows 11?

Every since Windows 7, I have been using this code to enable the "glass" effect on a window:

bool MUtils::GUI::sheet_of_glass(QWidget *const window)
{
/* Code to load "dwmapi.dll" and look up the required functions is excluded*/

//Enable the "sheet of glass" effect on this window
MARGINS margins = {-1, -1, -1, -1};
if(HRESULT hr = dwmExtendFrameIntoClientAreaFun(reinterpret_cast<HWND>(window->winId()), &margins))
{
qWarning("DwmExtendFrameIntoClientArea function has failed! (error %d)", hr);
return false;
}

//Create and populate the Blur Behind structure
DWM_BLURBEHIND bb;
memset(&bb, 0, sizeof(DWM_BLURBEHIND));
bb.fEnable = TRUE;
bb.dwFlags = DWM_BB_ENABLE;
if(HRESULT hr = dwmEnableBlurBehindWindowFun(reinterpret_cast<HWND>(window->winId()), &bb))
{
qWarning("DwmEnableBlurBehindWindow function has failed! (error %d)", hr);
return false;
}

//Required for Qt
window->setAutoFillBackground(false);
window->setAttribute(Qt::WA_TranslucentBackground);
window->setAttribute(Qt::WA_NoSystemBackground);

return true;
}

Result on Windows 7 looks like this:

https://i.imgur.com/P61ZnfK.png :cool:

Windows 8.1 and Windows 10 still looks sort of "okay":

https://i.imgur.com/Cfn1Dii.png :o

But on Windows 11 it looks like... that:

https://i.imgur.com/7UJwwxW.png :scared:

So, background is just not rendered at all on Windows 11, making the window totally transparent and looking kind of "broken". Any idea why that is?

What I'd actually like to have is a semi-transparent "smoked glass" effect, as in the Windows 11 startmenu and settings menus:
https://i.imgur.com/J1YaQlH.png

[xofaho]

As I know, the only way to enable glass effect in Windows is to install a third-party software, but Idk which exactly.

[LoRd_MuldeR]

Please note that this question is not about "third-party software" to modify the look of Windows 11 itself or that of someone else's software.

It is about getting Windows 11 to correctly render my software with the "smoked glass" effect, just as a vanilla Windows 11 already does in the Start menu or in the "Settings" app.

For now, I have disabled DwmEnableBlurBehindWindow() on Windows 11, which is better than a fully transparent background...