특정게시판에서만 네이버 스마트 에디터에 숨어있던 코드

html보기로 보니 아래와 같은 소스가  나타났습니다.

다른 게시판은 아래 코드가 없는데 특정 게시판에만 아래와 같은 소스가 삽입되어있는 이유가 무얼까요?

오픈된 사이트도 아니고 개발중인 사이트이며, 저만 접속중입니다.

아래 코드는 어떤 기능을 하나요..?

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