The W3C Link Checker, when I allowed 10 levels of recursion (more than needed) and set it to send the Referer, reported a link as broken because the URL included the fragment identifier <#top>. I fixed those allegedly broken links by adding id="top" to the body element but that shouldn't be necessary. Top is an implicit destination and does not require an id or name attribute. See HTML5, section 5.6.9, 2d series of steps, step 7 ("[i]f fragid ["the fragment component of the resulting parsed URL"] is an ASCII case-insensitive match for the string top, then the indicated part of the document is the top of the document; stop the algorithm here") (insertion per id., step 1) (http://www.w3.org/TR/html5/single-page.html#scroll-to-fragid). Therefore, the Link Checker should accept the fragment identifier "#top" (without quotation marks) as legitimate without an explicit destination as long as the part of the URL to the left of the fragment identifier's hash mark is legitimate.

For this bug report, I guessed the component and the version; the version is actually 4.81. The HTML5 text was as accessed last Sunday.