Reverting switch to 24hr time for events & tasks (v91.2.1)

[macho_]

My events & tasks began to display their time in 24-hour time format instead of 12-hour time format when my standard OS repositories upgraded me to Thunderbird v91.2.1.

I tried to look in the preferences for how to revert this change, but wasn't able to find it. Any pointers on how to do so would be appreciated.

[tanstaafl]

See https://support.mozilla.org/en-US/questions/1237962

Supposedly Thunderbird relies totally upon the systems time settings and you can't configure the calendar time settings separately. So check your systems time settings and see if they changed.

[epp]

I'm questioning whether this may be a bug in Thunderbird 91.x. When version 78 was installed, the date/time in the e-mail listing was in 12-hour AM/PM time. Once upgraded to 91, it reverted to 24-hour time, there are a lot of posts online about this. I've found no way to change it back so far.

[tanstaafl]

https://www.reddit.com/r/Thunderbird/co ... being_set/
https://forums.linuxmint.com/viewtopic. ... &p=2079760

Perhaps its a Linux specific issue. https://www.reddit.com/r/Thunderbird/co ... _on_linux/ is several years old (same problem occurred in 2018) but mentions a workaround of changing the launchers string from /opt/thunderbird/thunderbird to env LC_TIME=en_DK.utf8 /opt/thunderbird/thunderbird

Perhaps you could try that using your locales time zone.

[epp]

Code: Select all

~$ locale
LANG=en_US.UTF-8
LANGUAGE=
LC_CTYPE="en_US.UTF-8"
LC_NUMERIC=en_US.UTF-8
LC_TIME=en_US.UTF-8
LC_COLLATE="en_US.UTF-8"
LC_MONETARY=en_US.UTF-8
LC_MESSAGES="en_US.UTF-8"
LC_PAPER=en_US.UTF-8
LC_NAME=en_US.UTF-8
LC_ADDRESS=en_US.UTF-8
LC_TELEPHONE=en_US.UTF-8
LC_MEASUREMENT=en_US.UTF-8
LC_IDENTIFICATION=en_US.UTF-8
LC_ALL=

There is an /opt directory, but it's empty.

[tanstaafl]

The idea was to set the locale environment as part of launching Thunderbird, rather than beforehand. Whether or not it uses a /opt directory is a detail.

https://www.reddit.com/r/linuxquestions ... saying_12/

[macho_]

Posting back here because I found a solution:

A lot of the threads out there indeed dwell on LC_TIME, but this was a red herring for me because I already had it set to a 12-hour locale (en_CA.utf8).

But then I found the thread at the following URL which (to the extent I understood it) suggests that somewhere between versions 78 and 91 there was a change in the way the gsettings database is queried: https://bugzilla.mozilla.org/show_bug.cgi?id=1726464

What I had was this:
$ gsettings get org.gnome.desktop.interface clock-format
'24h'

It thus seems all I had to do to resolve this issue was this:
$ gsettings set org.gnome.desktop.interface clock-format 12h

So far all is back to normal, though I have not yet tried a reboot or anything.