Hi.
So, I started to have problems. I'm not sure if it started today or I just didn't notice it before. Tried 2 different files (that were created earlier), tried restarting my PC. Still occurs.

I've got animation. Rotation changes from angle1 to angle2 and back to angle1. I'm using smooth bezier curve between them.

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Now, I'm starting to move it all to right with offset ON. One of the transitions changes curve to linear. :/

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If I move it left (even without letting LMB go), the wrong transition moves to end of animation.

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On some bones it occurs always, on some it occurs randomly. Always occurs if I let LMB go and grab it again.
If I undo the changes, my selection changes to this. Not sure if it has anything to do with the problem, but the problematic keyframe is no longer selected for some reason. EDIT: Actually I'm sure now, cause if I select keyframes of few bones, it's always the problematic one which is deselected after undoing.

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I'm not sure if it's connected, but if I select all keyframes, trun on Adjust and edit first frame, the last frame doesn't adjust. The rest does. :/