Reproduction Steps: 1. Import attached project. 2. Open "Bug" audio mixer. 3. Rename any of the groups in it. 4. Undock the Audio Mixer tab and place it elsewhere. 5. Try to rename any of the groups again. Expected result: Easily able to rename a group. Actual result: Unable to rename groups. (GIF attached) Reproducible with: 5.5.2p2, 5.6.2p3, 2017.1.0p1, 2017.2.0b3 Not reproducible with: 5.4.5f1