My Thunderbird calendar refuses to display dates in European format, namely ''day-month-year''. I have read lots of helpful hints on the forums and tried everything, but nothing changes. My system is Ubuntu 25.04 with Cinnamon 6.4.8. Thunderbird version is 140.3.0esr (64-bit). Some of the suggestions refer to settings that are no longer there compared to earlier versions. For example, Settings > General > Language and Fonts has no format options. I have also used the config editor while TB was not running and added '''ntl.date_time.pattern_override.date_short''' and '''ntl.date_time.pattern_override.time_short''', without any effect. Dates in the calendar still always appear in the illogical American ''month-day-year'' format. This is confusing, to say the least ! Has a solution been found to EASILY select the locale and formats that should be used? At the moment, the settings are under different menus and in different locations, and TB seems to be making it as difficult as possible to get these set - permanently ! - to the user's preference.