The token mappers are a little unusual, in that they not only handle storage, but they also send the call to issue a token. Token issuing is performed via an asynchronous call to a system smart contract. Between sending the call and receiving the callback it was possible to launch a second token, because the mapper was not being locked.
As always, feel free to send us feedback or open a topic in our Github Discussions tab and share your thoughts so that the entire MultiversX community can hear you. If you have a great idea, share it with us and let's make it happen by implementing and integrating it in our ecosystem.
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