using import statements which contain dots (like import "./Controls" ) causes a crash of QtCreator when adding "QML Component" by dragging in QM-Designer

How to reproduce:
1) open attached project
2) open file BugQMLDesigner.qml in QtCreator
3) switch to Design
4) try to add another "MyButton" from QML Components
-> crash

using just import "Controls" in BugQMLDesigner.qml works.
Of course in this example there is no need for import "./Controls"
I simplified a complexer example where I needed import "../Controls" and observed that crash relates to the dots
Crash happens under Windows and Linux