43b978658e
When selecting a new date, we get a date object from the currently selected date before the change. If that month has less days than what was selected for the new month, `setDate` will wrap that to the following month since the old month is still selected there. For example: select any date in april (has 30 days) then select the 31th of january this will actually select the 1st of january since we first get setDate: 20xx-04-XX -> 20xx-04-31 (wrap) -> 20xx-05-01 setMonth: 20xx-05-01 -> 20xx-01-01 To fix this, use the additional parameters of setFullYear[0] to set all of them simultaneously 0: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/setFullYear Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>