Do we need type="text/css" for in HTML5

Specific cases to consider using the type attribute

While in HTML5 the type attribute is by no means compulsory, there are some exceptions where you might contemplate specifying it:

1. Teaching purposes: When educating budding programmers about MIME types, it signifies to them its theoretical importance.
2. XHTML5 Syntax: For achieving XML and HTML5 compatibility, you might use the type to abide by the stricter semantic rules.
3. Clearer Documentation: In big projects where documentation is crucial, denoting type can make the code clearer to new developers and non-programmers.

But for daily coding, it's advisable to cast off unnecessary attributes and stick with the neat, efficient HTML5 syntax.

Future-proofing and issues related to the type attribute

Though the current trend heavily leans towards omitting the type attribute, some concerns regarding future-proof changes still linger:

• Evolution of Stylesheets: As technology evolves unceasingly, new stylesheet languages may take the lead. Having type declared beforehand may serve as an easy bridge during transition phases.
• Different Styling Syntaxes: In documents where various styling languages could potentially coexist, the type attribute can help differentiate among them.

Despite these potential use cases, the existing standards including web browsers consistently treat <link> tags without type as CSS. Furthermore, without any DTD constraints for HTML5, the attribute is merely advisory.

How does the server determine the content type?

It's the HTTP response headers from the server that primarily dictate the content type. It's quite straightforward:

• Content-Type header: The server’s HTTP response includes this header, which unequivocally defines the type of content, superseding any type attribute in the <link> element.
• Browser Logic: Browsers prioritize HTTP headers over <link> attributes while discerning content types, rendering type even more redundant.

While deploying your crisp CSS files, verify your server sets the Content-Type header as text/css to steer clear of pesky MIME type conflicts.