embedding a gifv in a spoiler prevents it from playing

LD50

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matt has a problem

It's playing fine in the spoiler for me. Current Firefox release on Win7.

LD50

I can force it to play if I right click and hit 'show controls' and hit play there, but it doesn't auto play for me. I'm on chrome 58 windows 10.

Elvenshae

Chrome as well, and the spoilered version doesn't play for me, either.

BahamutZERO

autoplays normally in the spoiler for me as well in win10 firefox.