Does the DOCTYPE declaration have to be the first tag in an HTML document?
34634
Can comments appear before the DOCTYPE declaration?
16604
What's the purpose (if any) of "javascript:" in event handler tags?
89762
How can I determine the type of an HTML element in JavaScript?
131268
Is it OK to create the HTML first for an ASP.Net or ASP.Net MVC site?
51818
Why certain DOCTYPE declarations cause 100%-height tables and divs to stop working?
83998
What’s the difference between esc_html, esc_attr, esc_html_e, and so on?
11635
Disable warnings when loading non-well-formed HTML by DomDocument (PHP)
46478
Why is the first tag sometimes in the  tag of some questions?
93221
How is the tag chosen to prefix the title?
65996
When is a CDATA section necessary within a script tag?
51715
How can I prepend a tag to the beginning of several files?
129988
Is type="text/css" necessary in a  tag?
139881
why HTML Agility Pack HtmlDocument.DocumentNode is null?
47874
Should the HTML Anchor Tag Honor the Disabled Attribute?
107906
IE11 Document mode defaults to IE7. How to reset?
58990
The markup in the document following the root element must be well-formed?
97944
Javascript - Change html tag type