[whatwg] [WF2] action="mailto:" - encoding spaces

[Shadow2531]

<http://www.whatwg.org/specs/web-forms/current-work/#for-mailto>
<http://www.whatwg.org/specs/web-forms/current-work/#x-www-form-urlencoded> (#4)

In mailto URIs, %20 represents a space.

<form action="mailto:">
    <input name="subject" value="1 2">
    <input type="submit">
</form>

If you submit that form, "mailto:?subject=1+2" will be passed to the
mail client instead of "mailto:?subject=1%202". This results in "1+2"
in the subject field instead of "1 2".

Are UAs allowed to use %20 instead so things come out right, or must
mail clients decode + to a space? Thunderbird, M2, and Outlook express
don't decode +s.

RFC2368 is referenced, but it and application/x-www-form-urlencoded
that the mailto: form methods are referenced under conflict with each
other on whether a space should be encoded to %20 or +.

-- 
burnout426