"6. Accessible Name and Description calculation"
Should have a name rules for HTML label element which allows name calculation from subtree. Refer to Mozilla bug for more information https://bugzilla.mozilla.org/show_bug.cgi?id=453594:
Technically, a label shouldn't need a name because a label is just presentational and isn't actually a control used by the user. However, right or wrong, the reality is that labels are sometimes used for purposes other than labelling a control; e.g. a message.