Moc'ed file excluded from build after saving cpp file

I have exactly the same issue as in QTVSADDINBUG-555. However, when I try to migrate my project to Qt/MSBuild approach, I have the following error on some projects in my solution (not all of them) : "The following error occurred: Error converting project <project name>." (see attached screenshot "MSBuild migration error.png")

I have converted back my project in QMake Generated Project and try the convert it to MSBuild from this state, but the same error is displayed.

Is it possible to have more explanation about this error or what could be the cause?