When I wake my Mac-mini (with the latest MacOS updates), only multi-colored snow shows up on the HP display. Other users indicated the same issue with Windows, so it's not an OS issue. It looks like a lack of syncing between the HP monitor and the HDMI signal from the computer. A display problem, not a computer problem. But whomever answer these questions on this board isn't addressing the issue and recommends the usual "check your BIOS" etc. Not helpful.
My work-around: turn the display off, and turn it back on again: it restarts with a good picture. But this should be done by the display firmware, not the user.
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