http://bugzilla.opensuse.org/show_bug.cgi?id=1109379 http://bugzilla.opensuse.org/show_bug.cgi?id=1109379#c12 --- Comment #12 from Carlos Robinson <carlos.e.r@opensuse.org> --- I'm sorry to say that the issue is not solved in MozillaThunderbird-60.3.0-80.1.x86_64, at least on openSUSE 42.3 - I'll test 15.0 later. The date is still displayed as DD-MM-YYYY HH.MM, not respecting the setting that says "Regional locale (English (Denmark))" Then I tried: LC_TIME=es_ES@euro thunderbird & and the date format changes to DD-MM-YYYY HH:MM Next I tested: LC_TIME=es_US thunderbird and the date format changes to MM-DD-YY HH:MM So it seems to be following other locales, but not LC_TIME=en_DK.UTF-8. Has perhaps the "en_DK" format changed? How can we find out? That locale is supposed to be ISO, ie YYYY-MM-DD HH:MM (...) No, it has not changed. cer@Telcontar:~> LC_TIME=en_DK.utf8 date +'%x %X' 2018-11-10 13:39:59 cer@Telcontar:~> LC_TIME=en_US date +'%x %X' 11/10/2018 01:40:22 PM cer@Telcontar:~> "Help > Troubleshooting Information" Application Settings Requested Locales ["en-US"] Available Locales ["en-US"] App Locales ["en-US","und"] Regional Preferences ["en-DK"] Default Locale "und" Operating System System Locales ["en-US"] Regional Preferences ["en-DK"] I found this: <https://bugzilla.mozilla.org/show_bug.cgi?id=1426907> which seems to track the issue. Comment 59 has a workaround, but does not work for me: Telcontar:~ # ln -s /usr/share/i18n/locales/en_DK /usr/share/i18n/locales/root Telcontar:~ # echo 'root.UTF-8 UTF-8' | tee -a /etc/locale.gen root.UTF-8 UTF-8 Telcontar:~ # locale-gen If 'locale-gen' is not a typo you can use command-not-found to lookup the package that contains it, like this: cnf locale-gen Telcontar:~ # cnf locale-gen locale-gen: command not found Telcontar:~ # locale locale localectl localedef Telcontar:~ # Then: cer@Telcontar:~> LC_TIME=root.UTF-8 thunderbird & [1] 6620 cer@Telcontar:~> (thunderbird:6620): Gtk-WARNING **: Locale not supported by C library. Using the fallback 'C' locale. -- You are receiving this mail because: You are on the CC list for the bug.