Operating system: Windows 10 Home 1809
Graphics card: Intel UHD 630
Broken: 2.80, 552b2287db86, 2019-02-01
we have two bones, one is extruded from the previous one. add some keyframes to child bone, duplicate the keyframes, add some keyframes to parent bone, clear these newbie keyframes, even it has no keyframes, it shows animation.(the parent bone)
duplicate keyframes, add some keyframes for the parent bone, apply "clear keyframes" for the parent bone, play the animation and see parent bone moves even it doesnt have any keyframes. (save the blend file and reopen it, problem is vanished.)