Few problems have been more frustrating in the long term for me as the seemingly random action of keyframes at times. Many times they work exactly as expected, but occasionally, I'll see things like this (usually in the timeline's Keyframe tool):
Placing a new keyframe and then clicking Undo may bring back more than 1 keyframe or even move a different keyframe;
Splitting a clip with keyframes in only one section sometimes shows motion tracks in the newly-split clip that has no placed keyframes;
When manually creating complex motion/crop paths, sometimes a smooth motion or zoom suddenly jumps for no apparent reason.
Now, I hope the phantom/zombie keyframe issue can be solved like the vexxing pre-2015 audio/video split glitch and the pre-2018 timeline audio waveform display issue.
I did not document every kind of keyframe issue, but as far as I can tell, these problems are caused when keyframes somehow get added or shifted off of the frame boundary and into the "middle" of a frame. That was very much the cause of the A/V split, when clips would get corrupted by just editing or moving them on the timeline, and here keyframe misalignment also seems to wreak all kinds of havoc.
During my testing I also uncovered a couple of other issues, so I put them all in this video:
I would really appreciate it if other forum members can do these simple tests on their machines. I believe that the 3 keyframe issues happen on several earlier versions of PD, but I only tested the volume display and "atomic level" keyframe zoom crash on PD17 v2721 (in the video, these are tests 1 and 5).
The sample project is available for download here, and it's tiny since it only uses the Skateboard clip. I will report these if other people can confirm that the issues are present outside of my system.
YouTube/optodata
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