Event plugin displays incorrect Day of Week in topic

Environment

Discourse Version: v3.4.0.beta1 +271

Plugin Commit: e0c4bfef

Steps to Reproduce

Enter the date November 27 2024 into the date selector in the Events wizard – it will appear correctly as Wednesday in this view.

Upon creating the post / pushing the edit, it will appear in the topic as “Friday,” as shown in the following image:

https://i.imgur.com/9DoF67J.png

The issue does not seem to happen on refreshing the page — only when navigating to it from the calendar, or directly proceeding an edit. Although refreshing does not fix the problem as described in “SIDEPROBLEM” below.

Example

SIDEPROBLEM: on the Events Calendar homepage, this same day appears as Thursday… or Saturday… or Sunday in the Calendar, or the topic button that you can access from it — the association between days and positions in the calendar seems random.

Image to bug: https://i.imgur.com/KwaoIQU.png

Logs

https://i.imgur.com/8Z90VhN.png