qApp crashes after being deleted when hosted as a plugin and when focus application is changed

I've stumbled on a very particular bug that didn’t happened before with Qt 5.X.Y

We develop audio plugins with Qt compiled statically. Every time a instance of our plugins is loaded we increment a counter and when a plugin is unloaded, we decrement the counter. When it gets to zero, we delete the Qt app. This method has been working stable for the last 8 years.

Recently, using Qt 6.6.1 I’ve realised that if I delete the last plugin, and the Qt app is deleted, if you then switch the focus to another application, the host application of the plugin crashes on the following function:

0x155cddc8c invocation function for block in QCocoaWindow::setupPopupMonitor() + 24

As far as I could evaluate, this is a macOS bug only.

This is a tricky bug to provide an example on how to reproduce, we need to be able to load the Qt application as a plugin, delete the Qt Application and switch the app in focus. But I'm available to provide more information if necessary.