Guidelines and HOWTOs/Gammaray
KDAB GammaRay is a GUI app that allows you to inspect a running GUI app that uses Qt widgets or Qt QML. See https://github.com/KDAB/GammaRay and https://www.kdab.com/gammaray .
A video version is available https://www.youtube.com/watch?v=W6dVfn1nAzI