1810173 - Changing timezone of `Start` time doesn't change it for `End` time in same time zone

Status: NEW

(Calendar :: Dialogs, defect)

Description

[Ralf Jung]

Steps to reproduce:

Thunderbird 102.6.1

Since the recent-ish overhaul of the calendar, the behavior of the even editor when changing the timezone has become rather annoying: one has to now change the timezone twice, once for the "start" time and once for the "end" time. It is exceedingly rare that one would want those two to be in different timezones, so that is a rather frustrating default behavior.

To reproduce, create a new event, and then change the timezone of either the start or the end time.

Actual results:

The other time remains in the old timezone.

Expected results:

The timezone should apply to both start and end time.

Comment 1

[Thomas D. (:thomas8)]

Thanks Ralf, good point!
Confirming for TB 102.6.1 (64-bit), Win10. This has indeed regressed from TB 91.

STR

1. Calendar > New Event dialog > Options > Show Timezones
2. Event with start and end time, both in the same time zone
3. Click on Time zone of start time and change it to another time zone.

Actual result

• TB 91: Time zone (TZ) of both start and end time are changed (ok).
• TB 102: Only time zone of start time is changed (this bug). (Erratically on an unsaved event, they were changing in sync, but only once.)

Expected

Smart behaviour as in TB 91:

• Whenever both time zones are the same, changing start time's TZ changes both. Most events (except long travels) certainly end in the same time zone where they start, so that's a convenient default behaviour (as reporter points out).
• Changing end time's TZ will not change start time's TZ, so now they are different/decoupled
• Whenever start vs. end time zones are different, changing one will no longer change the other.

That looks like a perfectly smart and convenient behaviour to me, just does the right thing with least effort for the user.

Comment 2

[Alice0775 White]

Regression window:
Last good build:98.0b3 (BuildID=20220228212456)
First bad build:99.0b1 (BuildID=20220308191624)

However, I cannot find GOOD builds in Daily build (common-central).
The issue also exists in the common-central build 68.0a1 (BuildID=20190319090245).

I have given up on the bisection.

Comment 3

[Thomas D. (:thomas8)]

(In reply to Alice0775 White from comment #2)

Regression window:
Last good build:98.0b3 (BuildID=20220228212456)
First bad build:99.0b1 (BuildID=20220308191624)

Thank you!

Comment 4

[Magnus Melin [:mkmelin]]

It is exceedingly rare that one would want those two to be in different timezones, so that is a rather frustrating default behavior.

I don't know about that. It's very common for say flights, when you fly between different timezones.