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24h time format in Thunderbird

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Hi there. I know this question has been asked before, but none of the other threads have found suitable solutions, and unfortunately they are all archived, so I need to ask anew:

In Thunderbird 78.13.0 (the latest provided by my distro), the time format is 12h AM/PM. This is undesired.

OS system settings are 24h time format. System clock and all other apps display 24h time format. All except Thunderbird. This is regardless of "Application locale / Regional settings locale" option in TB preferences.

Date format does display correctly in Thunderbird (as per system settings).

So... I've scoured TB preferences menu and the web and there is no option to set this. I'd like to know if there's an environment variable within TB (i.e. through the "config editor") to set time format, and if so, what is the correct syntax.

Thanks!!

Hi there. I know this question has been asked before, but none of the other threads have found suitable solutions, and unfortunately they are all archived, so I need to ask anew: In Thunderbird 78.13.0 (the latest provided by my distro), the time format is 12h AM/PM. This is undesired. OS system settings are 24h time format. System clock and all other apps display 24h time format. All except Thunderbird. This is regardless of "Application locale / Regional settings locale" option in TB preferences. Date format does display correctly in Thunderbird (as per system settings). So... I've scoured TB preferences menu and the web and there is no option to set this. I'd like to know if there's an environment variable within TB (i.e. through the "config editor") to set time format, and if so, what is the correct syntax. Thanks!!

Chosen solution

Hi Stans,

Success!

I modified the /etc/default/locale file with a custom override for LC_TIME. In my case I set it to en_GB.UTF-8 and that did the trick!

For others with this issue, this is an article I found helpful: https://unix.stackexchange.com/questions/553679/set-clock-to-24-hour-format-for-all-users

Also, thank you Stans for clarifying the capital/lowercase time syntax! That is very helpful!

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All Replies (4)

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Thank you Stans for the reply.

I had seen this article before (linked in your response) but there is no mention of 24h clock in it. If I enter the HH symbol, will this continue to be 12-hour time?

Furthermore, these env variables do not exist in Thunderbird 78 (only 91+ as indicated). Am I simply S.O.L (i.e. is TB78 simply unable to display 24h time)?

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Unis_Torvalds [[#answer-145:3413|said]]

I had seen this article before (linked in your response) but there is no mention of 24h clock in it. If I enter the HH symbol, will this continue to be 12-hour time?

That's the idea. Capital H is for 24hr while lowercase h is for 12hr. The example output for HH:mm is 09:59 which is 24-hour format, isn't it?

Furthermore, these env variables do not exist in Thunderbird 78 (only 91+ as indicated). Am I simply S.O.L (i.e. is TB78 simply unable to display 24h time)?

TB 78 does display 24hr time. How do you have it setup, is it set to use Ubuntu's system regional settings? Have you set system-wide regional locale settings in Ubuntu or just for your user account? It should be system-wide for TB to pick it at startup. See https://blog.softhints.com/thunderbird-how-to-change-display-time-to-24h-format/#step3changethunderbirddateandtimeformatting

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Chosen Solution

Hi Stans,

Success!

I modified the /etc/default/locale file with a custom override for LC_TIME. In my case I set it to en_GB.UTF-8 and that did the trick!

For others with this issue, this is an article I found helpful: https://unix.stackexchange.com/questions/553679/set-clock-to-24-hour-format-for-all-users

Also, thank you Stans for clarifying the capital/lowercase time syntax! That is very helpful!