4d1292ac__1_6_Embedded_content___HTML_5__Default_implied_ARIA_semantic
[Language feature] input element with a type attribute in the Image Button state [Restrictions] Role must be either button, link, menuitem, menuitemcheckbox, menuitemradio, or radio [Default implied ARIA semantic] 
button role
3.2.5.1.6 Embedded content — HTML 5
Default implied ARIA semantic