thanks for the profile Todd.
its very complex working through things that can and do happen with third party hardware.
there are many many combinations of devices systems, hardware - and its not possible to provide any 'rules of thumb' when things dont work.
you probably havent discovered a 'bug' but a combination of things that doesnt work with a specific system setup. ( and there will be many of them ). just as there are also many combinations that do work.
So -its really really important that i get as many details as possible.
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what you described happens on early and older systems when their display resolutions are not setup correctly. or two monitors are connected at different refresh rates - and other things like this.