Repro steps:
1. Build WebGL player.
2. In player, press right arrow on keyboard once to advance to next scene (generic Particle test scene).
3. Press right arrow again to load skinned mesh renderer scene.
4. Observe that the player hangs.

Expected result: the player does not hang :)

Notes:
- Since 5.5 projects don't open in earlier versions, I recreated the project, but could not repro in 5.3.5p5, 5.4.0p1, and 5.5.0b4.
- Thought it might be multi-scene editing related, so redit it again for 5.3.5p5, 5.4.0p1, and 5.5.0b4; still couldn't repro.