No, they don't. It depends on the MIME type. The spec says application/xhtml+xml pages MUST be parsed with draconian error handling, but pages with text/html need not. Note that text/html is deprecated for XHTML 1.0 but invalid for XHTML 1.1.

In other words, if we use XHTML 1.0 Transitional served with MIME type text/html we shouldn't run into problems.

Of course, we're already scrubbing users' HTML, so I don't see why it would be too difficult to clean it using f.ex the tagsoup algorithm.

Makeshifts last the longest.

In reply to Re^2: let's have valid html by Aristotle
in thread let's have valid html by particle

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.