Someone sent me an event invitation message. When Thunderbird displays this message, there is a special part of the message which has the event details. The event details include "When", with the date and time when the event starts and finishes. Expected behaviour: the date and time includes a time zone, so that I can compare it to: a) the time zone of the event host, b) my current time zone, c) the time zone of the location where I will be when the event occurs, and d) UTC time, so that I can know when the event happens independent of time zones and daylight savings time rules. Observed behaviour: the date and time is displayed with no time zone, e.g. "2019-11-04 21:15 – 22:45". How can I configure Thunderbird to display a time zone with the event details? If there is no setting for this (and I suspect there may not be), should I file a bug ticket with a feature enhancement request for this time zone display? What I mean by "a special part of the message which has the event details": This is an outlined box within the message body. It has a blue header at the top. In this header, there is the text, "<Host name> has invited you to <event title>". Below that, the box has a left part in grey and a right part in white. The left part has labels like, "Title", "Location", "When", etc. When I look at the message source, I do not see HTML content for this event details box. I do, however, see a MIME message part that looks like this: {{{ --_000_b9217c07d661460693845db28d2047f3PMBX112W1CA1PEXCH112ICA_ Content-Type: text/calendar; charset="utf-8"; method=REQUEST Content-Transfer-Encoding: base64 QkVHSU46VkNBTEVOREFSDQpNRVRIT0Q6UkVRVUVTVA0KUFJPRElEOk1pY3Jvc29mdCBFeGNoYW5n ...[base64 text omitted]... QVINCg== --_000_b9217c07d661460693845db28d2047f3PMBX112W1CA1PEXCH112ICA_-- --===============0479938929717374914== }}} When I decode the base64 content, I get what appears to be a VCALENDAR record from Microsoft Exchange Server. It looks like this (abbreviated): {{{ BEGIN:VCALENDAR METHOD:REQUEST PRODID:Microsoft Exchange Server 2010 VERSION:2.0 ...[lines omitted for brevity]... BEGIN:VEVENT ...[lines omitted for brevity]... DTSTART;TZID=Eastern Standard Time:20191104T151500 DTEND;TZID=Eastern Standard Time:20191104T164500 ...[lines omitted for brevity]... }}} The VCALENDAR record includes a definition of the "Eastern Standard Time" time zone. From the VCALENDAR information I can do arithmetic, and see that the unlabelled time displayed by Thunderbird is in my local time zone. But I want not to have to remember this or figure it out each time I get an invitation. I want Thunderbird to label the event time with a timezone.