Pardon for the English. This is a bug which Magix support is aware of. It is related to DX12 acceleration and the Intel Integrated Graphics (iGPU) drivers. There are workarounds like turning off DX12 by selecting "Use DX9" but you then lose the performance advantages bought by DX12.
It is normally not present on PC's with a separate Nvidia or AMD graphics card. I find that openining a NEW BLUE effect plugin on the clip then resetting the NB Effect to "None" makes it behave normally.
This happens on all versions of VDL and VPX on my computer. Magix have not reacted to the problem because only a few users have reported it, so please send a ticket to Magix support with your experiences.