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How can I make the "add event" dialog in Lightning use 12-hour times?

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  • Last reply by Zenos

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The Add Event dialog in Lightning (on an iMac running OS 10.10.2 Yosemite) is displaying 24-hour times in the dropdown boxes. I need these to be in 12-hour format.

Also, the default calendar needs to be changed. Where are these preferences located?

The Add Event dialog in Lightning (on an iMac running OS 10.10.2 Yosemite) is displaying 24-hour times in the dropdown boxes. I need these to be in 12-hour format. Also, the default calendar needs to be changed. Where are these preferences located?

All Replies (1)

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I don't know what the acceptable setting values are, but you could experiment with

calendar.date.format

in the config editor. Tools|Options|Advanced|General→Config editor

Mine is set to 1 and it's faithfully copying the date/time format I use elsewhere, but that may just be coincidence. But I suspect it is simply the toggle between long and short date formats as offered in the Options GUI for the calendar.

Bear in mind that all those AM/PM indicators will eat up precious screen real estate.

Settings for the Calendar are under Tools|Options (on Windows); that'll be Edit|Preferences or Thunderbird |Preferences.

Tools|Options

Modified by Zenos