thunderbird-change-date-format.md

What to do Change the date format to an unambiguous format, e.g. yyyy-MM-dd

How?

• Click the three holizontal lines menu in the top right corner
• Select General, then scroll to the bottom of the page
• Click Config Editor...
• Type intl.date_time.pattern_override.date_short, select String, then click the + button at the right side of the line
• Enter yyyy-MM-dd and press the tick mark.
• Confirm that this setting is active by selecting Events and Tasks -> New Task: and checking the Start: and Due Date: fields.

Why? Thunderbird by default uses either the application locale of the regional settings locale, as shown in:

• Click the three holizontal lines menu in the top right corner
• Select General
• Select Date and Time Formatting

Affected version(s): All recent, e.g. 115.6.1

Solution in: https://enterprise.thunderbird.net/manage-updates-policies-and-customization/thunderbird-preferences-enterprise/customize-thunderbirds-date-and-time-formats

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