Middle align keeps jumping
When I have a group with middle applied and lose focus after moving it, it then jumps up. Really annoying and weird. Insanely awesome plugin btw.

![feb-07-2018 11-10-50](https://user-images.githubusercontent.com/6673900/35933392-c378ec08-0bf7-11e8-9b25-e72c722b2be8.gif)
