denjia2009 谢谢你提出这个问题! 准确地说，这个问题并不限于按键偏移的情况，而是由于在一个循环动画中，即使开始帧和结束帧的按键值相同，而且它的曲线手柄是直的，在缩放时也不能保持角度，除非手柄是水平的。
Thank you for raising the issue! To be precise, this issue is not limited to the case of offsetting keys, but is caused by the fact that in a loop animation, even if the keys at the start and end frames have the same value and its curve handles are straight, the angles are not maintained when scaling, except when the handle is horizontal.
However, this is indeed a factor that causes some extra efforts to adjust the duration of the entire animation, so I have created a ticket to improve this issue: EsotericSoftware/spine-editor 746
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