Is it possible to get a list of email addresses hosted on MS Custom Domains ?

Hello there,

I know the Custom Domains program is now no more in action, but actually all our company emails are under that program, most of them are under use, but some of them are lost, we forgot them, so is there a way I can get a list of email addresses we had under custom domains ?

We don't want to create anything new or remove existing ones, just a list of all emails we had under the hood ?

Looking forward for help.

Thanks!
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