- "htmlform-datetime-placeholder": "Used as initial placeholder text in \"datetime\" input boxes. This date and time MUST be formatted as a 4-digit year, 2-digit month, and 2-digit day, in the Gregorian calendar, separated with ASCII hyphen ('-') characters, followed by a space (or the letter 'T'), followed by a time formatted as a 2-digit hour 00 to 23, a 2-digit minute, and an optional 2-digit second, all separated by ASCII colons. You can localise the letters to your language or script, but you should not change the format.",
- "htmlform-datetime-invalid": "Used as error message in HTML forms. This date and time MUST be formatted as a 4-digit year, 2-digit month, and 2-digit day, in the Gregorian calendar, separated with ASCII hyphen ('-') characters, followed by a space (or the letter 'T'), followed by a time formatted as a 2-digit hour 00 to 23, a 2-digit minute, and an optional 2-digit second, all separated by ASCII colons. You can localise the letters to your language or script, but you should not change the format.\n\n* {{msg-mw|Htmlform-invalid-input}}\n* {{msg-mw|Apifeatureusage-htmlform-datetime-placeholder}}\n* {{msg-mw|Apifeatureusage-htmlform-datetime-toolow}}\n* {{msg-mw|Apifeatureusage-htmlform-datetime-toohigh}}\n* {{msg-mw|Htmlform-required}}",