Do I need role=“button” on a <button>?

Question

I\'ve noticed in all of Bootstrap\'s examples using button elements, they include role=\"button\" (and type=\"button\"), such as:

Answer 1

According to W3C Html5 Button

The missing value default is the Submit Button state.

If the type attribute is in the Submit Button state, the element is specifically a submit button.

Unless you're going to use buttons to submit a form, you need to explicitly set type="button" as omitting this, as stated in W3C specification, it will act as a submit button, will submit your form. To avoid unnecessary submits, you need to explicitly set type="button" to your s.

Since most of the bootstrap's buttons are for triggering a javascript function or similar behaviour, to avoid accidental unintentional submit behaviour upon code copy&paste and in the name of normalization with good practice, type="button" and role="button" attributes are added to