Intel's driver release in Aug 2017 for Intel 6,7, and 8 Gen procs claims to have addressed OpenGL issues with indirect displays.
Version: 22.20.16.4771
Release Notes:
https://downloadmirror.intel.com/270...leaseNotes.pdf
Excerpt: "Enabled OpenGL hardware acceleration when running Miracast or DisplayLink."
I have not tested yet, but will be doing so very soon. I suppose no luck for 4 and 5 Gen Intel proc machines at this time.
PeterB