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Cannot change Thunderbird Lightning to use 12 hour calendar format

Steven A. Falco
Steven A. Falco
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I am using Fedora Linux, KDE desktop. The Thunderbird calendar page shows all times on a 24 hour clock. I need this to be in a 12 hour AM/PM format.

I've tried exporting LC_TIME="en_US.utf-8" and LC_ALL="en_US.utf-8" but that doesn't make a difference.

The clock in my task bar does show 12 hour AM/PM format, so my desktop, in general, has the correct format, but the Thunderbird calendar appears to be ignoring that setting.

How can I force Thunderbird calendar to use a 12 hour AM/PM format?

I am using Fedora Linux, KDE desktop. The Thunderbird calendar page shows all times on a 24 hour clock. I need this to be in a 12 hour AM/PM format. I've tried exporting LC_TIME="en_US.utf-8" and LC_ALL="en_US.utf-8" but that doesn't make a difference. The clock in my task bar does show 12 hour AM/PM format, so my desktop, in general, has the correct format, but the Thunderbird calendar appears to be ignoring that setting. How can I force Thunderbird calendar to use a 12 hour AM/PM format?

Chosen solution

I found a workaround. I shut down thunderbird, then edited my prefs.js and added two lines:

user_pref("intl.date_time.pattern_override.time_medium", "hh:mm:ss a"); user_pref("intl.date_time.pattern_override.time_short", "hh:mm a");

When I restarted thunderbird it was using a 12 hour format.

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All Replies (1)

Steven A. Falco
Steven A. Falco Question owner
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Chosen Solution

I found a workaround. I shut down thunderbird, then edited my prefs.js and added two lines:

user_pref("intl.date_time.pattern_override.time_medium", "hh:mm:ss a"); user_pref("intl.date_time.pattern_override.time_short", "hh:mm a");

When I restarted thunderbird it was using a 12 hour format.