System Information
Operating system:
Graphics card:

Blender Version
Broken: (example: 2.80, master)
Worked: (2.79)

Short description of error

• set up a chain of bones
• add a targeless IK constraint to each bone in the chain

now you can grab each bone and move it around. I expect that all children of the grabbed bone just move along with the bone and all parents of the bone follow the targetless IK chain.

Exact steps for others to reproduce the error

• open the blend file and select the armature in Pose mode
• Select the leaf bone (Bone.003) and move it using 'G' and see that all is well
• Select the parent bone (Bone.002) and move it using 'G' and see that the child does not follow
• As soon as you release the mouse key, the child bone snaps into place

The very same setup worked in older Blender versions, i made a quick test on Blender 2.79 to be sure.