I had similar issue with some page components flipping when switching back to a tab. Very confusing when the HTML5 vcenter tab to the console of a server is showing flipped. Looks like an issue only in latest 78 release. Edge Beta (v77) doesn't show the same issue for me.
I had another post on here about the same issue. Turns out this is a known issue in the Chromium source. A fix has been developed, and being merged back in. The fix should show up in Edge Canary builds soon.