Warnings:
The “type” attribute for the “style” element is not needed and should be omitted.
The “type” attribute is unnecessary for JavaScript resources.
The first occurrence of ID “menu-item” was here.
The first occurrence of ID “main-content” was here.
The first occurrence of ID “html_block” was here.
The first occurrence of ID “attachment_54793” was here.
The “border” attribute is obsolete. Consider specifying “img { border: 0; }” in CSS instead.
The “language” attribute on the “script” element is obsolete. You can safely omit it.
This document appears to be written in English. Consider adding “lang="en"” (or variant) to the “html” start tag.
Errors:
An “img” element must have an “alt” attribute, except under certain conditions. For details, consult guidance on providing text alternatives for images.
Duplicate ID “menu-item”.
The “center” element is obsolete. Use CSS instead.
Element “div” not allowed as child of element “ul” in this context. (Suppressing further errors from this subtree.)
Duplicate ID “main-content”.
Duplicate ID “html_block”.
Bad value “"http://www.letsrun.com/news/2019/02/after-re-measuring-the-course-heres-definitive-proof-that-the-2018-abu-dhabi-marathon-was-short/” for attribute “href” on element “a”: Illegal character in path segment: “"” is not allowed.
Duplicate ID “attachment_54793”.
Element “tbody” not allowed as child of element “table” in this context. (Suppressing further errors from this subtree.)
End tag “div” seen, but there were open elements.
Unclosed element “center”.
Element “style” not allowed as child of element “body” in this context. (Suppressing further errors from this subtree.)
The value of the “for” attribute of the “label” element must be the ID of a non-hidden form control.
United States US
