In the shadow DOM implementation, custom items now use the ARIA application role if they're focusable, or the img role if they're not.
The region role is no longer used as a default for shadow DOM elements. In particular, this means that single-line text fields no longer have this role; they don't need a role, since they're represented in the shadow DOM by actual HTML input elements.
Custom role descriptions are now supported by both the shadow DOM and UIA implementations.
applicationrole if they're focusable, or theimgrole if they're not.regionrole is no longer used as a default for shadow DOM elements. In particular, this means that single-line text fields no longer have this role; they don't need a role, since they're represented in the shadow DOM by actual HTMLinputelements.