Why does this abbreviation "tl;dr" have a punctuation mark in it?

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Music by Eric Matyas
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Track title: Popsicle Puzzles

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Chapters
00:00 Why Does This Abbreviation &Quot;Tl;Dr&Quot; Have A Punctuation Mark In It?
00:29 Accepted Answer Score 11
02:36 Answer 2 Score 10
02:54 Answer 3 Score 4
05:04 Answer 4 Score 1
05:31 Thank you

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Tags
#punctuation

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