Week input — an ISO week

Expected: the first control shows week 38 of 2026 (14–20 September) and its picker selects whole weeks, Monday to Sunday. The empty control opens on the current week. The value is yyyy-Www.

Bounds

Expected: only weeks 36 to 40 of 2026 can be chosen in the first control; the second steps by fortnight from week 36.

Readonly, disabled and invalid values

Expected: readonly and disabled open nothing. The invalid values are sanitised to empty — 2027 has 52 weeks, so 2027-W53 does not exist.