Both are considered "recommend closure" flags. The duplicate reason is also one of the close reasons with which a post can be closed, and once you retract a close flag for any reason, you can't flag it again, for any reason. The fact that there's a separate option to link straight to the duplicate reason can make this a little confusing, but as your link ...


Code fences weren't supported until January 2019, so any post that used them before then had them rendered as simply inline code. You do need to edit and save in order for the post to be rendered using the new Markdown processor.

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