Setting a format for dates and times in Thunderbird

In my GNOME locale settings, the preview shows that dates are in the format YYYY-MM-DD and that times are separated by colons. However, in Thunderbird, these formats aren’t respected. I’ve scoured the Web, and there doesn’t seem to be a way to tell Thunderbird how to format things directly. You have to use the locale settings to do it. But Thunderbird also isn’t respecting the locale settings. I’ve also tried building custom locales, but neither GNOME nor Thunderbird seems to see them after I compile the new locales, even though command line tools do see them. Any ideas on how to get the dates and times formatted as desired in Thunderbird?

GNOME locale settings:

Dates and times in Thunderbird:

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I have not tried changing it in Thunderbird, but I prefer the DD-MM-YYYY format. I remember reading about this eons ago.

I am not sure if this is the link where I saw the instructions nor do I vouch for this content. It is really old.

Scroll down to “Configuring the date/time system settings on your computer” and the Linux section. Out of curiousity, I looked at the bug that is mentioned there. It is still open!

I hope this helps you. They may be a better way–I noticed mention of an extension to fix this–so it may be possible to just update the prefs.js.

As long as they don’t try commas for the decimal point like in Europe. If you have a SQL database it definitely won’t work. (I’ve been told that’s something SQL never got right.)

I’ve tried the methods listed on that page, too. Thunderbird still reads the en_DK locale formats differently than GNOME does, and refuses to even accept custom locales, edited by hand and compiled.

Sorry to hear that. I tend to avoid add-ons besides security/privacy ones, but I have seen other folks discuss the ‘Enhanced Date Formatter’ for Thunderbird. Maybe that will do what you want, but I have not tried it.

The fact that some of these add-ons exist seems to indicate there is a way to do it. If others know, I would be interested too.

I found the add-on you’re referring to, but it seems that when I try to install an add-on to Thunderbird, Thunderbird wants to download it to disk and either just be done with it or open it with another application instead of installing it. And if I choose Thunderbird as the other application to open it with, Thunderbird opens up a new email to compose, and attaches the newly-downloaded add-on file as an attachment to the new email.

This isn’t the first time I’ve had Mozilla add-ons not work on PureOS, either. PureBrowser won’t install language packs (I haven’t tried other browser add-ons), and always displays error pages from the server instead. There might be something wrong with PureOS’s copy of some Mozilla library.

I have had that problem too, though I actually only have a couple of add-ons for Thunderbird. (I do not allow links to be opened or remote content. Just text mail.) I do not like installing from a file either, but the trick is to install the .xpi from Thunderbird itself.

I should qualify my statement a little by mentioning that I am using Thunderbird from Mozilla, not from Purism. I think this should still work though:

Go to your Add-ons Manager page in Thunderbird and click the little cog icon on the right hand side, near the top. (It is the same place as “Check for Updates.” ) One of the options is “Install Add-on From File.” That has worked for me, as long as the add-on is compatible with the version.

Thunderbird ignores locale settings. I only uses LC_ variables to determine the locale name for particular category, and then takes values from its internal ICU/CLDR database.

So you are stuck with default values for a given locale. Changing locale values, or creating custom locales won’t do much either. More details (with some workarounds) over there:


So Thunderbird is unusable then? I guess it’s time to start looking for a new client again. It looks like the same issue applies to Firefox, which doesn’t surprise me. It’s by the same development team, obviously, and Firefox has been driving me up the wall for years. It’s so hard to find a decent Web browser these days.

As for the “workarounds”, I can’t find any on that page or the linked one that actually function.

I noticed something odd in T-Bird. If moving messages from one downloaded email account to another (folder to folder), it appears it uploads the email back to the host, then back down again. Odd that. (It was to folders in same window.)

(I noticed because at the bottom is started saying download ‘n’ of ‘nnn’ message and was going rather slowwwwllllyyy. (You’d think they could just move messages disk location to disk location and would be a lot quicker.)

If IMAP this makes some amount of sense in that the goal is to keep email sync’d on both sides. POP3 I would expect that kind of move to stay local.

Since I followed the recommendations of and, AND presuming that’s what they said, that probably explains it. Thanks!

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