Illustrator Window Disappears When Changing Screen Focus
When I switch focus from my center screen where illustrator 2020 is, on my mac mini running Catalina 10.15.3 on three LG monitors, to the screen to my left, Illustrator vanishes.
It's not minimized, it's just gone, I have to click on the icon in the taskbar to pull it back up. It looks like it's there in Mission Control, but if I click on it, it just goes back to being invisible/unclickable.
This is a pain when I'm cross referencing. If I click the icon to get it back, it'll stay there if I don't click into it, and it'll stay there if I start using it. It's after I use it that it disappears.
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A similar behavior happens for me even with a single display attached, often on launch — the app launches and immediately vanishes. I have to click the taskbar button at least once (and sometimes several times in a row) to make the window appear.
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Reanon commented
Happens to me as well, very annoying!