Is type="text/css" necessary in a \ tag?

All about MIME types

Historically, the type attribute was used to indicate the MIME type of the linked content. However, in HTML5, this attribute is not necessary for stylesheets because text/css is the default value. Although modern browsers understand <link> elements with a rel attribute of stylesheet to be text/css, they're like the smart kid in school, they just get it!

Is backward compatibility an issue?

Concerns may arise about compatibility with older browsers when dropping the type attribute. Testing shows older browsers like Internet Explorer can handle omitting type="text/css" under HTML5. So, there is no need to worry about compatibility issues when leaving out this attribute.

Cases where type="text/css" may still be required

In some specific scenarios, for example in SharePoint 2013, specifying type="text/css" may still be required due to certain system-level constraints. Apart from these, it might help avoid unnecessary resource fetching by browsers where non-CSS MIME types are used.

Future-proof coding and adherence to standards

Keeping type="text/css" can be viewed as commitment to explicitness and future-proofing your code. Although HTML predominantly uses CSS for stylesheets, it's like a "just in case" umbrella for unexpected HTML showers.

Optimizing code complexity and performance

Eliminating type="text/css" not only streamlines your HTML files but also boosts browser performance as there will be less to parse. This tactic fits perfectly with the ethos of modern-day minimalistic design and efficient coding practices.

Avoiding conflicts with MIME types

Taking caution to avoid inconsistencies with the MIME type is crucial. If type="text/css" is present, it should correspond with the CSS content being linked.

Looking beyond the type attribute

The evolution of HTML syntax has lowered the spotlight on attributes like type and focused more on rel and itemprop. The role of the type attribute in functionality has hence diminished.