The tag implication #61384 conversational_sign -> sign is pending approval.

Reason: This tag seems to be for when a character is holding up a sign that says what they want to say, Wile E. Coyote style.
post #4022507
Therefore, there must be a sign in the post. I'm hesitant to imply text, since it's theoretically possible for such a sign to only use pictographics.