If it matters my system has (unused9 Intel 4000 graphics on yhr MB and a (used) Geforce card (for higher resolution).

Does somebody know if this is this a known problem? 

There must be some logs with debugging information.  But where will I find them? I may consider reporting to FZ, but developers will prbbably require logs.  And if it is a known issue already reported, there is no idea in doing so. 
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