I remember bug 1976026 and how nothing guaranteed a new window is visible when it becomes active. Visibility on windows seemed racy and this test is probably another place where it shows up. This intermittent being windows-only so far aligns with that.
Bug 2002097 Comment 3 Edit History
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I remember bug 1976026 and how nothing guaranteed a new window is visible when it becomes active. Visibility on windows seemed racy and this test is probably another place where it shows up. This intermittent being windows-only so far aligns with that. This also only shows up with slow CCOV tasks right now. Here's the follow-up I filed back then about visibility issues: bug 1978353.