GRUB_TERMINAL=console was not in the file either, so I added it. This is the the file with that added.
Same result, black screen and stall with these changes and default boot. Recovery mode with the nomodeset line boots to terminal. startx brings up desktop but still no OpenGL.
Code:
GRUB_TIMEOUT=10 GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian` GRUB_HIDDEN_TIMEOUT_QUIET=true GRUB_DEFAULT=saved GRUB_CMDLINE_LINUX_DEFAULT='' GRUB_TERMINAL=console
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