tl;dr: This system has some additional protections, but also some of the same weaknesses as a typical workstation email setup. Understand the below conversation in that context.
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@@ -30,7 +31,7 @@ If targeting a user on the *local* system, there is nothing to reject it there.
Just blocking these messages outright will break some mail setups. Basically, the summary is: you probably don't want to have untrusted users on your local system.
There is an esoteric case where the From: line contains multiple addresses. See the conversation on the [mailing lists](mailing-lists) page for more.
There is an esoteric case where the From: line contains multiple addresses. See the conversation on the [mailing lists](running-mailing-lists) page for more.