HTML5: disabled vs. readonly form fields

Form fields can be rendered as noneditable by setting the disabled or the readonly attribute. Be aware of the differences:

disabled fields

• don’t post to the server
• don’t get focus
• are skipped while tab navigation
• available for button, fieldset, input, select, textarea, command, keygen, optgroup, option

Browser specific behavior:

• IE 11: text inputs that are descendants of a disabled fieldset appear disabled but the user can still interact with them
• Firefox: selecting text in a disabled text field is not possible (copy&paste does not work)
• Firefox cancels any JavaScript events at a fieldset[disabled]

readonly fields

• post to the server
• get focus
• are included while tab navigation
• only available for input[type=text], textarea