Thunderbird date format?

I have ubuntu 10.04 running Thunderbird 14.0

How do I change the date format to international standard? (eg; 2012-07-26)

My system date already shows this format.

How to get YYYY-MM-DD HH:MM date format in Thunderbird 60

sudo ln -s /usr/share/i18n/locales/en_DK /usr/share/i18n/locales/root
echo 'root.UTF-8 UTF-8' | sudo tee -a /etc/locale.gen
sudo locale-gen
LC_TIME=root.UTF-8 thunderbird

Why LC_TIME=en_DK.UTF-8 thunderbird no longer gives this date format

Thunderbird and Firefox now use CLDR (Unicode Common Locale Data Repository), which does not have the ISO 8601 date format in en_DK.

References

• http://kb.mozillazine.org/Date_display_format
• https://bugzilla.mozilla.org/show_bug.cgi?id=1426907
  • https://bugzilla.mozilla.org/show_bug.cgi?id=1426907#c59 - The solution shown above
• https://bugzilla.mozilla.org/show_bug.cgi?id=1509096
  • https://bugzilla.mozilla.org/show_bug.cgi?id=1509096#c0 - Explanation about en_DK not working

I know of 4 ways to alter TB's date. Take your pick ;) (you just need 1)

• Quick Locale Switcher add-on for TB. Might be the easiest one.

• Mozilla's official documentation in changing date formats.

  In Thunderbird, choose Tools –> Options –> Advanced –> General > Config Editor

  Options:

  mail.ui.display.dateformat.today    
  mail.ui.display.dateformat.thisweek     
  mail.ui.display.dateformat.default  
  

  Values:

  V   Meaning                                 Example date and time
  0   No date                                 10:23 AM
  1   Your system's long* date format         Friday, December 31 2003 10:23 AM
  2   Your system's short* date format        12/31/1999 10:23 AM
  3   Year and month, separated by a slash    1999/12 10:23 AM
  4   Abbreviated day name                    Fri 10:23 AM 
  

• Change the startup command to

  export LC_TIME=en_GB.UTF-8 && thunderbird %u
  

  (Dash Main Menu > Internet > Thunderbird > Properties) Ofcourse change en_GB.UTF-8 to what you need

• Change your custom locale (/usr/share/i18n/locales) as explained on ubuntuforums.org.

Does depend on what you want to achieve - in Ubuntu 12.04 I got stuck with US locale settings (mm/dd/yyyy), wanted to switch to UK (dd/mm/yyyy), and couldn't find any tips.

Then I stumbled on system settings-> language support -> regional formats tab, change to English (United Kingdom). Easy!

Hope this helps someone

Unfortunately those answers don't show you how to set the date to YYYY-MM-DD format.

If you follow these instructions, setting the LC_TIME variable to en_DK.utf8 (I'd advise putting it in a script that calls Thunderbird) it will show YYYY-MM-DD HH:MM in the message view and give you the option of using YYYY-MM-DD in the calendar as the 'short' format.

http://kb.mozillazine.org/Date_display_format

Since Thunderbird 60.0 you need to set LC_TIME as stated in the other answers but you now also need to change the "Date and Time Formatting" option in the advanced preferences in the "General" tab.