A question about user signatures

I only just recently added a signature to my user profile, and there seems to be some inconsistency as to which of my posts include it and which do not. What's going on?

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"It's what people know about themselves inside that makes 'em afraid." - Clint Eastwood as The Stranger, High Plains Drifter (1973)

If your post is too long it can take over the signature space. That’s what I find.

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I’m here only on Mondays, Wednesdays & Fridays. That’s why I’m here now.

Signatures show once per page unless you change your settings

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Letterboxd

Sean is correct in that it shows once per page per user.