E.g. [youtube]https://www.youtube.com/watch?v=qWMgG5mlWys[/youtube]
Here's how to do it properly:
1. Click this button
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2. Go to your youtube video. I'll be using this one.
https://www.youtube.com/watch?v=JGkXfy60r7Y
3. Copy anything that comes after the = sign. For this video it's https://www.youtube.com/watch?v=JGkXfy60r7Y
4. ?????
5. Profit