I recently asked a question Backyard experiments to falsify the Flat Earth theory which has become much more popular than I originally anticipated, and has since been closed as a duplicate of What is the simplest way to prove the Earth is round?. Ordinarily I wouldn't mind too much that it was marked as a dupe since both questions are useful in their own right and the titles at least are clearly similar.
Today someone emailed me with a piece of info that should have been posted as an answer, but he said he didn't have the reputation to post since the question is protected. I resolved to post it on his behalf, but then I realized that it is not possible to add answers to duplicate questions. I suppose the idea is that the new answers should be added to the other question, but it doesn't seem to fit as well there, which makes me think that perhaps it shouldn't be a duplicate after all (although it is certainly a useful related reading).
As one commenter points out, there is a difference of wording - "show the Earth is round" vs. "show the Earth is not flat". My question is geared specifically to collecting practical experiments or observations that disprove the falsifiable physical component of the Flat Earth Theory espoused by the FES, not to showing the earth is round in the abstract. (There is also a social component, that is, showing that NASA is not involved in a coverup, but that's not as on-topic here.) The other question appears to have a more theoretical focus (probably "simplest" in the title was interpreted as "conceptually simplest"), and contains experiments like Eratosthenes that only work if you have already accepted the round-earth model to some degree (one of the answers on my question uses three-point Eratosthenes to circumvent this issue).
It doesn't appear that the question has quite finished its active period, and I would request that it be reopened. Would it be alright if I add a notice at the top pointing to the other question, but with less forceful wording than "this question is a duplicate"?