The CR HTML 5 spec has ambiguous wording regarding the display of the placeholder attribute in input elements (http://www.w3.org/TR/html5/forms.html#the-placeholder-attribute):

"User agents should present this hint to the user, after having stripped line breaks from it, when the element's value is the empty string and/or the control is not focused (e.g. by displaying it inside a blank unfocused control and hiding it otherwise)."

The use of "and/or" is ambiguous and, in fact, different browsers have implemented different behavior for blank, focused fields: some display the placeholder and other do not. Moreover, it makes no sense to display the placeholder when the input element is not empty, regardless of the focus state.

The nightly 5.1 draft (http://www.w3.org/html/wg/drafts/html/master/forms.html#attr-input-placeholder) has changed the language, but not for the better:

"User agents should present this hint to the user, after having stripped line breaks from it, when the element's value is the empty string or the control is not focused (or both), e.g. by displaying it inside a blank unfocused control and hiding it otherwise."

It eliminates the ambiguity (using "or" instead of "and/or"), but in a way that is inconsistent with the example (which is no longer a parenthetical). If the example is accurate, then "and/or" should have been replace with "and", not "or". Moreover, "or" (and the accompanying "(or both)" makes no more sense than before: an unfocused input element that is not empty should not display the placeholder. Finally, if the example ("e.g.") is supposed to be a restatement of the requirement, then "e.g." should be replaced with "i.e.".