Added new rule with an explanation (as per hilariousandco's suggestion):
33. Posting plagiarized content is not allowed.[e]
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33. This includes both copying parts or the entirety of other users' posts or threads and copying content from external sources (e.g. other websites) and passing it as your own.
Also, since SaltySpitoon pointed out, added the "Need confirmation if rule is still active." marker on the following rule:
Also, added SaltySpitoon in the credits.