When I joined I received a confirmation message and then two welcome messages which lacked the Content-type and Content-transfer-encoding fields. That's not a big problem because many email clients (Thunderbird in my case) can handle those mails by specifying a default character encoding.
However, the mail notifications from forum replies have these two fields:
Content-type: text/plain; charset=iso-8859-1
Content-transfer-encoding: 8bit
But the content is encoded as UTF-8, so it should be:
Content-Type: text/plain; charset=UTF-8
As we're going to be using Japanse A LOT
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Thanks and keep up the good work!