I don't see this particular problem listed- so I will.
newest upgrade to AE 2018 The "eyeball' button in preview is off when you open the window.
I admit I am not used to using this button at all as I always want to see the video.
But Anyway this gave me a few hours of mysterious frustration as caching doesn't seem to work the same with this off.
Frames turn green but only when you scrub frame by frame. Then they don't appear because the little eyeball is turned off!
just sayin. look out for this if you have black preview and green bar on timeline.
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