TRy this addon:

• https://addons.mozilla.org/en-GB/thunderbird/addon/super-date-format/

Although it says it works for versions 10 to 21, I can get it to work in 45.2

In order to install a downloaded extension, please do the following:

• Click the menu button New Fx Menu and choose Add-ons.
• Drag your downloaded XPI file to the Add-ons Manager tab and drop it.

or

• Click the menu button New Fx Menu and choose Add-ons.
• Click the gear icon at the top-right corner to the left of the search box and select Install Add-on From File…
• Locate the XPI file you downloaded and click Open.
• You may need to restart Thunderbird when prompted.

For more detailed instructions and information about installing add-ons, see Installing an Add-on in Thunderbird.

Thanks for the suggestion. But it doesn't seem to be quite what I need.

I like to apply different date values to day, 7 days and older messages.

I've used the about:config to change the date values as follows:

day: no date (0)

week: abbreviated day name (4)

older: system's short* date format (2)

I would like the older messages without the time. Just to make the column easier to read. Unless I've misunderstood the add-on, I can't see how to use the add-on without also removing the time from the day and week.

I agree that while the add-on permits much flexibility in formatting the date and time display, it doesn't seem to offer conditional formatting, that is, based on the age of the message.

Suggest you post a request on bugzilla. You will need to register if not done before.

• https://bugzilla.mozilla.org/index.cgi?

Only time, plus four date time variants, but no option for Date only. Request additional sixth option to only show date. currently the five available options are indicted in this link:

• http://kb.mozillazine.org/Date_display_format