Operating system: Windows 10
Graphics card: GTX 1070
Worked: >= 2.79
Short description of error
Translating the last bone in the chain everything works well (it actually rotates all the bones in the targtless IK chain). The problem is to Translate other targetless IK bone in the middle of the chain, causing the last bone not to update in realtime, but applies correctly at the confirmation.
Exact steps for others to reproduce the error
Press G to move the hand bone from the blend file. It'll work correctly. Select the lowerArm bone and repeat the process, pressing G to translate it. The hand won't update until you confirm the action.
Probable related issue: T61621