DokuWiki sends emails automatically at various occasions (password mails, subscriptions, etc.). These emails are usually sent as HTML Mime Multipart mails. This means the mails contain the content in a simple plain text format as well in a nicer formatted HTML format. Mail Clients then choose which format they understand. If you do not want this advanced formatting, you can disable it with this option. Mails then will be sent in plain text only, just as in older versions of DokuWiki.
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