weird flickering issue

Bug report

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Detailed steps to reproduce the problem

  1. As far as I know, just run iTerm

What happened

For some reason, my iTerm window flickers at an unpredictable rate. It's as if the background color is becoming subtilely lighter and then returning again. It is very faint, but it is noticeable, especially at fullscreen. Not sure at all what causes it, and it appears to be semi-regular in period, but not completely. At first I thought I was having some kind of brain episode and maybe I should try remembering my name or who the president is, but then I caught it with the quicktime recorder, so it is a real thing. Seems to only be iTerm. Wish I could give you more to go on than that, but I've attached all the things here, so hopefully that counts for something.

What should have happened

It shouldn't flicker like that.

wa