V13: Every month in the datepickers in Umbraco Engage starts on a Sunday

jsteenbeek · November 14, 2025, 8:42am

Every month in the datepickers in Umbraco Engage starts on a Sunday.

We observed this over multiple environments. All self hosted Umbraco v13.

As a developer I would love it when every month would start on a Sunday, but that’s not the world we live in.

sebastiaan · November 14, 2025, 9:11am

Oh that’s a weird one! Probably best to report an issue here:

jsteenbeek · November 14, 2025, 11:06am

Done. Thanks.

github.com/umbraco/Umbraco.Engage.Issues

Every month in the datepickers in Umbraco Engage starts on a Sunday

opened 11:05AM - 14 Nov 25 UTC

jsteenbeek

### Which Umbraco Engage version are you using? (Please write the *exact* versio…n, example: 13.2.0) 13.6.1 ### Which Umbraco version are you using? (Please write the *exact* version, example: 13.5.2) 13.9.2 ### Issue summary The datepickers in Engage show invalid dates, the first of the month is always a Sunday. <img width="1602" height="754" alt="Image" src="https://github.com/user-attachments/assets/fbf8fac5-0a62-48ae-a9d9-a7d4bc48a169" /> We have observed this over multiple environments. ### Specifics _No response_ ### Steps to reproduce Open a date picker: <img width="1602" height="754" alt="Image" src="https://github.com/user-attachments/assets/fbf8fac5-0a62-48ae-a9d9-a7d4bc48a169" /> ### Expected result / actual result The first of November is a Saturday

FuelAgency · October 15, 2026, 12:10am

Are you running Uskinned? We found a back-office .hidden style introduced by Uskinned in Umbraco v13 sets adjacent-month days to display:none, causing this issue.