Wrong calendar display in Identify for non-English languages

[carnifex]

Platform: Website

Browser: various

URLs: https://www.inaturalist.org/observations/identify

Screenshots of what you are seeing:

Description of problem:

Step 1: select a non-English language (I tried it for German and Spanish)

Step 2: go to Identify view

Step 3: filter for exact date

Result: the calendar shows non-existing dates (shift by one day) and the weekday abbreviations are not translated

Could this be due to different definitions of the ‘first day of the week’ (Sunday vs. Monday)?

[carnifex]

Possibly related to this bug, so I am adding it here:
In the German layout, the dates are now translated, but still shifted by one day - however, only (as far as I could see) when selecting dates during creation/editing of collection projects:

(correct would be >>Di 14<<)

On any other parts of iNaturalist, and also in the (Android-)app, weekdays are correctly assigned.

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Calendar (inaturalist.org/calendar/USERNAME):

Editing observation:

Filter in Explore:

Filter in ID-Module: