As far as I can tell, this issue pertains to QuickTime movie files that use the Animation CODEC. If your movie uses the Animation CODEC, use After Effects, Premiere Pro, Media Encoder, or Shutter Encoder (donation-ware) to transcode the movie file to Apple ProRes 422 HQ if the movie uses Animation or Apple ProRes 4444 with Alpha if the movie uses Animation with Alpha (also called "Animation+"). If rendering a movie from After Effects, use either the "High Quality" Output Module Template or the "High Quality with Alpha" one. If using an older version of After Effects that only has "Lossless" or "Lossless with Alpha", go into the Video Options and change the CODEC from Animation to Apple ProRes 422 HQ or Apple ProRes 4444. Note: transparency, or an alpha, requires using Apple ProRes 4444. As ProRes, the movie file should open immediately in Photoshop. I think this qualifies as a bug. While Apple dropped support for Animation when it deprecated QuickTime as a system driver for time-based media back in 2013, Adobe has been supporting it directly. As far as I am aware, support for Animation hasn't changed.
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