one that immediately comes to mind is poll options.

i've clicked and read too many polls with way more options than necessary.

did you know that the ideal poll option count is 3?

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also, people who post ultra-high resolution photos.

it's a good idea to resize them to around 800 px max width or height.

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also, people who simply type a post number as a reply to a reply.

that post number indicates that that responder should go and read the post #whatever ...

i just don't like that. i haven't found the specific reason yet.

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are there any other best practices we should type about?