I got them all! Two identical ones and one part 2. Looks like it still works! :D

Funny thing to note, the timestamps are: Apr 16, 2018 - 08:12:51 Apr 16, 2018 - 08:12:55 Apr 16, 2018 - 08:13:21 Looks like it's not a minute after all?

Hurray! I guess that means I won't need to test the refresh then. Maybe someone sneakily removed it. It was definitely a minute before. xD

Yeah, I remember it being a minute too! Glad it works, though c: Thank you for helping me test it out!

Thank you! And hurray for ongoing improvements. xD

@ Skolletta I had a chance to test it more with a friend.

There doesn't appear to be any time limit on sending a new mail. Literally sent her two mails that were 1 second apart. But there is still a 1 minute wait between replies to an existing mail. However, the refreshing trick works! And it unfortunately also makes it possible to spam a person's inbox with identical replies just by refreshing every minute to resend your reply. [edit]Also, you can just send someone a new message and mash the reload button to keep sending them duplicates of that message. Yikes!

Oh, the hilarity. XD I'm glad the trick does work when the error pops up!

Yes :)

Added it to the first post, thank you! :D