Frequent crashes in Qt6WebEngineCore

[JFritzle]

Describe the bug

I am observing since longer time and since several commits ago, that QMS crashes from time to time during initialization and before application gets ready for user interaction. This happens on all operating system, Windows, Linux and macOS.

Sometimes it happens at 2 subsequent runs of QMS, sometimes it does not happen for days.
But when it happens, always Qt6WebEngine is involved.

What have you done to circle down the problem?

At least since 1.19.0. But maybe some releases before.

To Reproduce

Unfortunately not reproducible!

1. Run QMS with debugger
2. Cross fingers
3. Almost good luck and no crash, sometimes bad luck and crash

Expected behavior

No crashes at all.

Screenshots

Attachments

Tracebacks

Windows crash - built with Qt 6.10.1 from todays development version
Console output at crash time:

...
2026-02-06 18:21:09.078 [debug] FF QTransform(type=TxScale, 11=10 12=0 13=0 21=0 22=-10 23=0 31=-629215 32=6.10199e+06 33=1)
2026-02-06 18:21:09.078 [debug] RR QTransform(type=TxScale, 11=0.1 12=0 13=0 21=0 22=-0.1 23=0 31=62921.5 32=610199 33=1)
2026-02-06 18:21:09.618 [debug] Sanity test passed.
2026-02-06 18:21:09.621 [debug] CMapDraw::saveMapList()
2026-02-06 18:21:09.621 [debug] CMapDraw::saveMapList(cfg)
2026-02-06 18:21:09.628 [debug] CMapDraw::saveMapList()
2026-02-06 18:21:09.628 [debug] CMapDraw::saveMapList(cfg)
2026-02-06 18:21:09.636 [debug] CDemDraw::saveDemList()
2026-02-06 18:21:09.644 [debug] CDemDraw::saveDemList(cfg)
2026-02-06 18:21:09.647 [debug] CMapDraw::saveMapList()
2026-02-06 18:21:09.648 [debug] CMapDraw::saveMapList(cfg)
2026-02-06 18:21:09.656 [debug] CDemDraw::saveDemList()
2026-02-06 18:21:09.656 [debug] CDemDraw::saveDemList(cfg)
2026-02-06 18:21:09.660 [debug] CMapDraw::saveMapList()
2026-02-06 18:21:09.661 [debug] CMapDraw::saveMapList(cfg)
2026-02-06 18:21:10.454 [debug] CDemDraw::saveDemList()
2026-02-06 18:21:10.472 [debug] CDemDraw::saveDemList(cfg) 

Stack trace:

[0x0]   Qt6WebEngineCore!QtWebEngineCore::Compositor::unlockBindings+0x1538c   0xf64d999e0   0x7ffba864f6d5   
[0x1]   Qt6WebEngineCore!CrashForExceptionInNonABICompliantCodeRange+0xed65d5   0xf64d99b40   0x7ffba8648db3   
[0x2]   Qt6WebEngineCore!CrashForExceptionInNonABICompliantCodeRange+0xecfcb3   0xf64d99bb0   0x7ffba8658c3d   
[0x3]   Qt6WebEngineCore!CrashForExceptionInNonABICompliantCodeRange+0xedfb3d   0xf64d99be0   0x7ffbab5b0318   
[0x4]   Qt6WebEngineCore!sqlite3_dbdata_init+0xe04d68   0xf64d99d30   0x7ffba6e317a4   
[0x5]   Qt6WebEngineCore!simdutf::get_available_implementations+0x1064564   0xf64d99d80   0x7ffbaa34bcf2   
[0x6]   Qt6WebEngineCore!GetHandleVerifier+0x7de8f2   0xf64d9aba0   0x7ffbaa359460   
[0x7]   Qt6WebEngineCore!GetHandleVerifier+0x7ec060   0xf64d9ac80   0x7ffbaa34b7cc   
[0x8]   Qt6WebEngineCore!GetHandleVerifier+0x7de3cc   0xf64d9acd0   0x7ffbaa351e5c   
[0x9]   Qt6WebEngineCore!GetHandleVerifier+0x7e4a5c   0xf64d9ae20   0x7ffbaa34edd5   
[0xa]   Qt6WebEngineCore!GetHandleVerifier+0x7e19d5   0xf64d9aee0   0x7ffbaa359460   
[0xb]   Qt6WebEngineCore!GetHandleVerifier+0x7ec060   0xf64d9b0d0   0x7ffbaa3555d9   
[0xc]   Qt6WebEngineCore!GetHandleVerifier+0x7e81d9   0xf64d9b120   0x7ffbaa355f1b   
[0xd]   Qt6WebEngineCore!GetHandleVerifier+0x7e8b1b   0xf64d9b290   0x7ffbaa355c9a   
[0xe]   Qt6WebEngineCore!GetHandleVerifier+0x7e889a   0xf64d9b2e0   0x7ffba5b3edb9   
[0xf]   Qt6WebEngineCore!QtWebEngineCore::TouchSelectionMenuController::qt_metacast+0x2e979   0xf64d9b310   0x7ffbaa368d57   
[0x10]   Qt6WebEngineCore!GetHandleVerifier+0x7fb957   0xf64d9b340   0x7ffbaa368e5c   
[0x11]   Qt6WebEngineCore!GetHandleVerifier+0x7fba5c   0xf64d9b3b0   0x7ffba9ac9dff   
[0x12]   Qt6WebEngineCore!CrashForExceptionInNonABICompliantCodeRange+0x2350cff   0xf64d9b3e0   0x7ffba9ae8f66   
[0x13]   Qt6WebEngineCore!CrashForExceptionInNonABICompliantCodeRange+0x236fe66   0xf64d9b450   0x7ffba9ae8a2e   
[0x14]   Qt6WebEngineCore!CrashForExceptionInNonABICompliantCodeRange+0x236f92e   0xf64d9b690   0x7ffba5a2ec1a   
[0x15]   Qt6WebEngineCore!QtWebEngineCore::AutofillPopupController::updateModel+0x135a   0xf64d9b760   0x7ffba37857c8   
[0x16]   Qt6Core!QObject::event+0x68   0xf64d9b7d0   0x7ffba4ab3701   
[0x17]   Qt6Widgets!QApplicationPrivate::notify_helper+0x151   0xf64d9b8d0   0x7ffba4ab27fe   
[0x18]   Qt6Widgets!QApplication::notify+0x156e   0xf64d9b900   0x7ffba3739931   
[0x19]   Qt6Core!QCoreApplication::notifyInternal2+0x101   0xf64d9bda0   0x7ffba373c0b3   
[0x1a]   Qt6Core!QCoreApplicationPrivate::sendPostedEvents+0x203   0xf64d9be10   0x7ffba44e74bf   
[0x1b]   Qt6Gui!QWindowsGuiEventDispatcher::sendPostedEvents+0xf   0xf64d9bf00   0x7ffba38d92e0   
[0x1c]   Qt6Core!QEventDispatcherWin32::processEvents+0x90   0xf64d9bf30   0x7ffba44e7439   
[0x1d]   Qt6Gui!QWindowsGuiEventDispatcher::processEvents+0x19   0xf64d9f0b0   0x7ffba3740414   
[0x1e]   Qt6Core!QEventLoop::exec+0x1c4   0xf64d9f0e0   0x7ffba3737e8a   
[0x1f]   Qt6Core!QCoreApplication::exec+0x16a   0xf64d9f180   0x7ff6f7d56c5b   
[0x20]   qmapshack!main+0x85b   0xf64d9f1e0   0x7ff6f8428790   
[0x21]   qmapshack!qtEntryPoint+0x30   0xf64d9f710   0x7ff6f8427286   
[0x22]   qmapshack!invoke_main+0x21   (Inline Function)   (Inline Function)   
[0x23]   qmapshack!__scrt_common_main_seh+0x106   0xf64d9f7a0   0x7ffca368e8d7   
[0x24]   KERNEL32!BaseThreadInitThunk+0x17   0xf64d9f7e0   0x7ffca434c53c   
[0x25]   ntdll!RtlUserThreadStart+0x2c   0xf64d9f810   0x0  

macOS crash - built with Homebrew's Qt 6.10.1 from development version some days ago
Console output at crash time:

Stack trace thread 0:

Stack trace thread 1 and subsequent:

Desktop

• OS: any
• QMapShack Version: at least since 1.19.0
• Window Manager: -

Additional context

[kiozen]

QtWebEngine is a trouble maker. It's just my opinion, never really debugged it to the root, but the main problem is it's deployment as extra package apart from the rest. This makes it very easy to have a binary different version than the rest. And that usually causes those strange crashes as described. But this is just my wild guess.

[eyzdh]

I found an other way to install qt for macOS without building with cmake, homebrew or macports.
But th Size of the QTWebEngineCore is much bigger and looks a bit different to Homebrew.
In my Case QT 6.11 Beta 3 but with QT 6.10.1 was the same.

QtWebEngineCore.framework/Versions/A:

in QMS - size is 257.1 MB

in homebrew folder - size is 432.7 MB

my other way, folder has the same size of 547.3 MB

my other way, in QMS has the same size of 545.8 MB

I don't know what is better and why this happened but just to know.