It's been reported in Reddit and on the Best Buy Spin 713 Chromebook reviews page. Here is the reddit link:
https://www.reddit.com/r/chromeos/comments/iv0u7e/acer_spin_713_screen_glitch/The the screen blink or glitch happens once an hour or so for about one second. It's not a total blackout but the screen will shift slightly and then go back to frame.
It's very annoying and makes me wonder if it could get worse. Lots of owners have noticed it. I've reported it to Acer Support and just wondering if anyone has heard of a BIOS upgrade etc. that would stop it. I am using Chrome version 88 and check for updates daily.
It's not predictable when the blink/glitch happens so that makes it tough to make a video of the occurrence. This is an almost perfect Chromebook except for that. I'm hoping for a fix soon. I could still take this one back for a full refund but have faith the Acer programming staff will develop a patch/fix.