Since when did the word "cap" become slang for lying?

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I think the first time I heard it was around 2017ish?

Since it was my friends I heard it from, I thought it was based off a Captain America meme that was currently going around or something.
Watch our "BLEACH Can't Fear Your Own World" full fandub:
https://youtu.be/a2s_RdYM_pE?si=5kHTTbvJX4CY8Zk8