问题
Is it correct practice or valid syntax to use other tags inside a <title>?
An example for multi-language title
<html lang=en>
<title>Some title in English and a <i lang=fr>word in French</i></title>
回答1:
See http://www.w3.org/TR/html401/struct/global.html#h-7.4.2:
Titles may contain character entities (for accented characters, special characters, etc.), but may not contain other markup (including comments).
(my emphasis)
回答2:
No, it may not
http://www.w3.org/Provider/Style/TITLE.html
回答3:
You can try to use whatever you want, but it will all be used as title string, without any additional parsing/processing from the browser (if that's what you expect). RFC says you have to resist from placing markup in title, though.
回答4:
TLDR: The <title> tag (1) must contain text (it must not be empty), (2) must only contain text (i.e. no other elements), and (3) must contain text that is not just white-space.
In HTML 5, the Content Model of the title element is:
Text that is not inter-element white space.
where inter-element white space is any Text node that is either empty or only contains sequences of space characters:
- U+0020 SPACE
- U+0009 CHARACTER TABULATION (tab)
- U+000A LINE FEED (LF)
- U+000C FORM FEED (FF)
- U+000D CARRIAGE RETURN (CR)
来源：https://stackoverflow.com/questions/12168806/is-it-allowed-to-use-other-tags-inside-title