Calendar shows Monday as first day of week, even with en-US and Imperial units set

🚧 THIS IS A TICKET MIGRATED FROM UPVOTY. The original ticket and comments will be available for a limited time over at:
https://abrp.upvoty.com/b/report-a-bug/calendar-shows-monday-as-first-day-of-week-even-with-en-us-and-imperial-units-set/
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The calendar display continues to show Monday as the first day of the week, even when language is set to English (United States) and units are set to Imperial. This layout is extremely uncommon in North America, and is a bit confusing.