An old plugin, refurbished so it can be made public, is now available. MultiSMTP had been written to configure more than one SMTP in WordPress with some specific features:
- quickly switch the current SMTP to one of the ones configured
- rotate the SMTP used while sending the emails
To be honest, I don’t remember exactly why it was written, probably for fun or to support someone with limited SMTP capabilities, but able to get more than one.
Anyway, it seems to work. See the official MultiSMTP plugin page.
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