[1] [DFN[[CODE(URI)@en[[[attachment:]]]] [[URL]]]] は、 [[Opera Mail]]
で内部的に用いられています。

* 例

[3]

[PRE(XML example code)[
<[QN@en[omf:showheaders] [http://www.opera.com/2003/omf]] href="attachment:/41/headers.html">すべてのヘッダーを表示</omf:showheaders>
]PRE]

[SRC@en[[[Opera]] 8.5]]

[4] 
[PRE(HTML example code)[
<div class="headers"><object type="application/vnd.opera.omf+xml" data="attachment:/2/headers.xml">Mail headers</object></div>
<div class="plainpart"><object id="omf_body_part_1" type="application/vnd.opera.omf+xml" data="attachment:/3/plain.xml">Mail body</object></div>
]PRE]