double click not recognized when issued by Logitech software

Logitech's mouse software allows the user to program mouse buttons with double click functionality. With such a setup, pressing the button causes Logitech's mouse software to emit two consecutive left click events without any (or a miniscule) pause between them.

Up to and including all 6.8 releases this was recognized by Qt as a double click, meaning the usual cascade of events "press, release, double click, release" was emitted.

Starting with 6.9.0 Qt only emits "press, release, press, release", no "double click" anymore.

To visualize the events I've modified the widgets/lineedits example & added overrides for mousePressEvent & mouseDoubleClickEvent. The only thing they do is dump the events via qDebug(). In Windows' DebugView utility I get the following with Qt 6.8.3 when using such a programmed mouse button:

00001345	13:23:36.458	mouse PRESS QMouseEvent(MouseButtonPress ts=20942968 LeftButton pos=254,256 scn=254,256 gbl=1214,712 dev=QInputDevice(QPointingDevice("core pointer" Mouse id=1 buttonCount=3))
00001346	13:23:36.458	mouse DOUBLE CLICK QMouseEvent(MouseButtonDblClick ts=20942968 LeftButton pos=254,256 scn=254,256 gbl=1214,712 dev=QInputDevice(QPointingDevice("core pointer" Mouse id=1 buttonCount=3))

With 6.9.0 I get:

00001348	13:25:27.904	mouse PRESS QMouseEvent(MouseButtonPress ts=21054421 LeftButton pos=282.667,251.333 scn=282.667,251.333 gbl=1243,707 dev=QInputDevice(QPointingDevice("core pointer" Mouse id=1 buttonCount=3))
00001349	13:25:27.904	mouse PRESS QMouseEvent(MouseButtonPress ts=21054421 LeftButton pos=282.667,251.333 scn=282.667,251.333 gbl=1243,707 dev=QInputDevice(QPointingDevice("core pointer" Mouse id=1 buttonCount=3))

I'm attaching the modified example files for easier reproduction.

The software I'm using is Logitech G HUB 2025.5.730277, which is the default software for Logitech peripherals.

Users of my application MKVToolNix reported this in this bug report. I do not know if they're also using a Logitech mouse or something else.