I am pretty sure in the shot when boba fett alerts jango to Obi wan that it isn't there.
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Than I don't see him bump into anything to cause it but there it is like less than 15 seconds into the scene.
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I dunno maybe we are seeing re-shoots with the dent. WHO KNOWS?
But glad to say watching that scene very carefully I had one of my other burning questions answered....do Jedis wear boxes or briefs? And you would think they would be WHITE....Obi-wans undies are turely darkside briefs 
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