Playback slider/timestamp freezes (mostly) when selecting too far in the future

[handre]

Minor annoyance: When clicking around in the playback slider, usually when far in advance of the already played portion, will freeze the playback-progress slider and timer (the song plays just fine, but visual indicators cease). Here's how to reproduce it:

1. Start playing a song.
2. Skip deep into the song
3. Watch as slider and timer freeze.

Works best when song has just loaded (I suspect the bug could be stated as "skiping into a part of the song not yet downloaded", but can't confirm -- test with a slow connection). Tested on spotify web player in google chrome 53.0.2785 / windows 10.