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Currently it's impossible to broadcast a command twice within a certain period of time, but that only applies to the alias of the command used, and not any other aliases. If it's feasible to do this it would be nice to stop things such as the below screenshot from occurring.
Unfortunately, different commands have different ideas of what is and isn't equivalent. You'd have to code it separately for each command. We actually already do this for some commands, but apparently !om isn't one of them.