YouTube Loves XKCD
So… XKCD posted this comic a few days ago:
And today, when I tried replying to a comment on YouTube, I couldn’t. Nothing happened. I checked Firefox’s javascript errors and saw this:
Error: commentPreviewEnabled is not defined
Source File: http://s.ytimg.com/yt/js/base_all_with_bidi-vfl58055.js
Line: 1244
So I just typed, in my address bar:
javascript:commentPreviewEnabled=true;void(0);
and lo and behold, this appears when I click “reply”!
Notice “Audio Preview”? Yeah, that’s a new one… Now, this made me want to investigate that Javascript file mentioned in the error I got. I saw it mentioned the file http://s.ytimg.com/yt/swf/textreader-vfl58051.swf, so I downloaded it and ran it through an SWF decompiler to get a look at the code. I saw this, in a function package named “com.google.youtube.texttospeech.TextToSpeech”:
flash.external.ExternalInterface.addCallback(”speakText”, _loc2, _loc2.speakText);
I know it doesn’t look like much to the untrained eye, but basically it’s making a function called “speakText” available to Javascript.
In other words… YouTube read the XKCD comic about audio previews of comments… and actually decided to implement that feature.
Maybe it’s a joke. Maybe I caught something I wasn’t supposed to see. But it’s funny as hell 
of course I had to make a YouTube video about it…
*update*
Yep, they implemented it!
