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Ever so often, there is a suggested edit that I choose to edit. However, when I click submit, nearly always I will get the notice saying the post was edited by someone else and that my edit must be a radical change to override their's.
This is often times annoying as I just put in effort to fix a post only to be prevented from doing it. I understand the reasoning for my edit needing to be more of a change, but I think we should prevent people from editing a suggested edit or even just not show it while someone else is editing.
As for how, maybe when someone clicks the "Edit" button, hide the suggested edit from the queue for (say) 5 minutes. If they click "Cancel" in the meantime, just "unhide" it for others to see. Maybe we could use AJAX to ping the server every 5 minutes to say we're still editing. If it doesn't receive the ping, then it could assume they closed out of it, and then it could be "unhid".