Mantiplot.bat standalone pyhthon raises cannot find Qt platform plugin "windows"

I am trying to use the python environment set up by mantidplot.bat to run an interface directly for example %run on Windows 64bit.

This gives:
This application failed to start because it could not find or load the Qt platform plugin “windows” in “”.

MantidWorkbench 6.0.0 ist running fine.

The Qt bug here has been fixed after release 6.0. There was also a small bug in the launch script for Drill. There is a fix that will appear in the nightly in a few days: Protect against window flags set to None by martyngigg · Pull Request #31361 · mantidproject/mantid · GitHub

Thanks for fixing it.