Regressions after updating to Qt 6.3.0

[stdevCrow]

The view is the following:

As you can see there are many elements overlaping others.

With the release of Qt 6.3.0, major changes to the QML engine were introduced, with the most important ones being the Qt Quick Compiler (see here, here and here), which compiles QML into native C++.
However, that comes with some drawback: not everything can be compiled into C++ (details here again), and so the QML code must be adapted following some guidelines, mainly for QML type compilation.

So, although the project compiles fine with Qt 6.2 series, doing so with Qt 6.3 gives the following warnings just by opening the executable:

Binding on background is not deferred as requested by the DeferredPropertyNames class info because one or more of its sub-objects contain an id.
Binding on contentItem is not deferred as requested by the DeferredPropertyNames class info because one or more of its sub-objects contain an id.
Binding on popup is not deferred as requested by the DeferredPropertyNames class info because one or more of its sub-objects contain an id.
Binding on popup is not deferred as requested by the DeferredPropertyNames class info because one or more of its sub-objects contain an id.
Binding on popup is not deferred as requested by the DeferredPropertyNames class info because one or more of its sub-objects contain an id.
Binding on popup is not deferred as requested by the DeferredPropertyNames class info because one or more of its sub-objects contain an id.
Binding on background is not deferred as requested by the DeferredPropertyNames class info because one or more of its sub-objects contain an id.
qrc:/ui/qml/Components/Delegates/DelegateDestinationList.qml:94:5: QML TextField: Binding loop detected for property "text"

[stdevCrow]

UPDATE: Also, the executable now does not close when you click the X, at least on Windows. It remains opened in the background.

[stdevCrow]

After diving a little more, I found that the problem is precisely related to the new QML Type Compilation (qmltc) (see Bug Report #98439).

[stdevCrow]

🚨 IMPORTANT UPDATE: As of Qt 6.3.0, the Qt 6 official documentation regarding the QMLTC says the following:

Warning: qmltc is currently in a Tech Preview stage and might not compile an arbitrary QML program (see Known Limitations for more details). When qmltc fails, nothing is generated as your application cannot sensibly use the qmltc output. If your program contains errors (or unsolvable warnings), they should be fixed to enable the compilation. The general rule is to adhere to the best practices and follow qmllint advice.

[olemis]

@stdevCrow What's qmllint advice in our particular case ?

[stdevCrow]

Binding on background is not deferred as requested by the DeferredPropertyNames class info because one or more of its sub-objects contain an id. 
Binding on contentItem is not deferred as requested by the DeferredPropertyNames class info because one or more of its sub-objects contain an id. 
Binding on popup is not deferred as requested by the DeferredPropertyNames class info because one or more of its sub-objects contain an id. 
Binding on popup is not deferred as requested by the DeferredPropertyNames class info because one or more of its sub-objects contain an id. 
Binding on popup is not deferred as requested by the DeferredPropertyNames class info because one or more of its sub-objects contain an id. 
Binding on popup is not deferred as requested by the DeferredPropertyNames class info because one or more of its sub-objects contain an id. 
Binding on background is not deferred as requested by the DeferredPropertyNames class info because one or more of its sub-objects contain an id.

As u can see there's no indication of where the error is, but the list grows when I open more pages (and related bindings are resolved). So I'm just naming all parent objects of there's at least a child with an id explicitly set.