Hi, I am not sure if this is a bug or I am doing something wrong. When tweening keyframes, using the snap FK to IK bone, it seems that it only causes the IK bone to snap to the old FK position. I am assuming that it causes this, because the keyframe in front of the tween frame only has a FK keyframe inserted. Is this normal? I ask this, since I do not recall this happening when using Rigify.
Here is a simple example of a character's left leg kicking.
1. Select the thigh fk bone and insert a keyframe on frame 1.
2. Goto frame 15, rotate the fk thigh bone so that the foot is pointing up in the air and add a keyframe there.
3. Next, goto frame 8 and and click on snap ik button, so that the IK bone is positioned with the fk foot bone. Notice how the button properly positioned the IK bone to the fk bone.
4. Using the IK foot bone, position the leg so that the knee is bent.
5. Now try clicking on the snap fk bone button, hopping that it will snap to the ik bone, but instead the IK bone snaps to the old fk position.