Preact compatibility

I use abstraction over react-motion https://github.com/maisano/react-router-transition/ to control routing with react-router4 and encountered with optimization problem. In the React everything is fine, but with Preact (aliases preact/preact-compat in webpack) the route starts rendering a lot of times until animation finishes. By debugging I found that the problem in the TransitionMotion methods willEnter/willLeave which are responsible for the animation. Do not understand why the React and Preact handle these case in different ways.
btw, I tried to switch to preact-motion and the story is the same.

I don't know maybe it's Preact problem, well, if so, please let me know.

Start with the TransitionMotion methods willEnter and willLeave mentioned in the report, then reproduce the behavior through react-router-transition using the stated preact/preact-compat webpack aliases. Compare the React and Preact cases and determine whether repeated route rendering occurs during animation; document the cause or confirm the relevant compatibility issue.

Written by the indexing model from the issue text.