No matter what combination of settings for Windows regions and languages, FF region download and navigator.userAgent, the placeholder text (as in, the text that shows before any value is entered, or when attribute value="") for an input field of type date always shows non-localized MM/DD/YYYY.

Reproduce: 1. Put 'data:text/html, <input type="date">' into the FF location. 2. Notice the text box shows 'mm/dd/yyyy' regardless of Windows and FF settings 3. Click in the box, select a date from the date picker, the result will be properly localized (e.g., select English (Canadian)/en-ca, or Chinese (Simplified)/ch-zh) and the date selected clearly doesn't match MM/DD/YYYY format.