User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.7.8) Gecko/20050511 Firefox/1.0.4 Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.7.8) Gecko/20050511 Firefox/1.0.4 Firefox misinterprets --[anything not null]> as a comment end tag for all DOCTYPEs (see http://htmlhelp.com/tools/validator/doctype.html) except: <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN"> <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML//EN"> This is best explained by example. The following HTML code, in an HTML file that has any current DOCTYPE except the two above... <!-- A -- B <p>C</p> --> <!-- D - - E <p>F</p> --> <!-- G -- H <p >I</p> --> ... should be displayed as empty space, since it consists of three HTML comments. However, Firefox displays it as... C --> I --> The "-- B <p>" is being misinterpreted as a comment end tag (-->). This does not happen in the second comment because of the space between the two hyphens. The third comment shows that the misinterpreted ">" does not have to be part of a valid tag. Reproducible: Always Steps to Reproduce: See 'Details' above. Actual Results: See 'Details' above. Expected Results: See 'Details' above.
The second <!-- ends the first which is correct parsing (it is the first occurence of -- that ends a comment, not --> ). See http://www.w3.org/TR/REC-html40/intro/sgmltut.html#h-3.2.4 *** This bug has been marked as a duplicate of 229974 ***