1972904 - Task reminder dialogue window doesn't appear anymore (started w/ TB 139.0)

Status: RESOLVED FIXED

(Calendar :: General, defect)

Description

[CL1]

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:139.0) Gecko/20100101 Firefox/139.0

Steps to reproduce:

Have used Thunderbird since 2010, have used Tasks almost as long. When TB 139 installed in 5/2025, task reminder dialogue stopped appearing when task date is satisfied. I posted this on reddit TB at https://www.reddit.com/r/Thunderbird/comments/1kox7v7/2025_thunderbird_stopped_showing_task/ . Solution was temporary, as follows: "3 horizontal lines at upper right corner->Settings->Calendar->Show the reminder dialogue (X)." This fix lasted about a week-> Task reminder dialogue has been seen again for 3 weeks. My new attempts to apply the fix were accompanied by unselecting and reselecting reminder dialogue, involving or not involving rebooting TB and rebooting my Windows 11 64-bit laptop computer. It appears TB 139 has broken Task reminder dialogue window- it always appeared before 139 at expected times, and now it never appears (except for the first time using the mentioned temporary fix),

Actual results:

At 6/18/2025 I haven't seen the Task reminder dialogue window for several weeks. TB 139 email works fine. I only use TB email and TB tasks.

Expected results:

Since TB 139 (5/2025 for me), every task that meets its date requirement should bring up the TB Task reminder dialogue window and let me see the task and allow me in the dialogue to delete it or postpone it. Currently using TB 139.02 6/18/2025.

Comment 1

[CL1]

(In reply to CL1 from comment #0)

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:139.0) Gecko/20100101 Firefox/139.0

Steps to reproduce:

Have used Thunderbird since 2010, have used Tasks almost as long. When TB 139 installed in 5/2025, task reminder dialogue stopped appearing when task date is satisfied. I posted this on reddit TB at https://www.reddit.com/r/Thunderbird/comments/1kox7v7/2025_thunderbird_stopped_showing_task/ . Solution was temporary, as follows: "3 horizontal lines at upper right corner->Settings->Calendar->Show the reminder dialogue (X)." This fix lasted about a week-> Task reminder dialogue has NOT been seen again for 3 weeks. My new attempts to apply the fix were accompanied by unselecting and reselecting reminder dialogue, involving or not involving rebooting TB and rebooting my Windows 11 64-bit laptop computer. It appears TB 139 has broken Task reminder dialogue window- it always appeared before 139 at expected times, and now it never appears (except for the first time using the mentioned temporary fix),

Actual results:

At 6/18/2025 I haven't seen the Task reminder dialogue window for several weeks. TB 139 email works fine. I only use TB email and TB tasks.

Expected results:

Since TB 139 (5/2025 for me), every task that meets its date requirement should bring up the TB Task reminder dialogue window and let me see the task and allow me in the dialogue to delete it or postpone it. Currently using TB 139.02 6/18/2025.

Comment 2

[CL1]

Added info from original reporter: In case this bug is related to the little bit of exaggerated nature of my accumulated tasks over 10+ years, my task list has 4 expired tasks, 24 unexpired tasks, and 57 tasks that repeat (with various repeat patterns such as daily, weekly, monthly, and various repeat counts like 3 months, 6 weeks, etc.). Keep in mind these events reliably opened the reminder dialogue window until Thunderbird 139 loaded into my Windows 11 in May of 2025.

Comment 5

[Francesco]

Confirming based on two duplicates.

I'm not familiar with tasks, to me they just look like events where the end date has been replaced by a due date.

I switched the option "Show missed reminders for writable calendars" on, created a task with a reminder based on the due date, and closed the application while the reminder was expected. In the end the reminder showed up, not immediately on restart, but a few minutes later.

Can someone give exact details to reproduce the problem on a freshly added task:

• Is "Show missed reminders for writable calendars" set? It should be due to bug 1988288? Note the pref default value was changed in bug 1934069 in TB 135, so that doesn't explain a behaviour change in TB 139.
• Is the reminder based on the start or the due date (sorry, I don't know how it's meant to work)?
• Is the application running when the reminder is expected? If not, does it show up after the application is started again?

Comment 6

[dasepp]

(In reply to Francesco from comment #5)

Can someone give exact details to reproduce the problem on a freshly added task:

• Is "Show missed reminders for writable calendars" set? It should be due to bug 1988288? Note the pref default value was changed in bug 1934069 in TB 135, so that doesn't explain a behaviour change in TB 139.
• Is the reminder based on the start or the due date (sorry, I don't know how it's meant to work)?
• Is the application running when the reminder is expected? If not, does it show up after the application is started again?

I just reproduced it again by creating a new task:

• The option "Show missed reminders for writable calendars" is set for me
• I set the reminder to n minutes before the task starts
• If the application is closed while the reminder is expected it never again shows for me. not immediately after I start the application and also not if an event reminder triggers the reminder window later. If the application is running while the task reminder triggers then (and only then) it does show as intended for me.

I just realized something though:
For my tasks (both new and old) I did not set a due date. Also status is set to not specified.
If I do set a due date it seems to work. Then I suddenly get reminders even when the reminder was triggered while the application was not running. At least while I was still between start and due date.
So it might be thunderbird "thinking" that the task is already over and it doesn't need to show reminders anymore?
Is a tasks status considered in any way for reminders?

Some additional info:
I am currently on version 140.2.1esr using a local calendar so no sync or anything like that for me. Both new and old tasks behave the same for me since some past update (I don't know which update specifically though - just that reminders did work on the very same tasks before).

Comment 7

[Francesco]

I really don't know how it's meant to work and whether the optional due date is just a "re-badged" end date of an event.

According to this code
https://searchfox.org/comm-central/rev/25a5e99e1e75363df8b21c0257a56ce7d10f9b38/calendar/base/src/CalAlarmService.sys.mjs#489-498
the "ongoing" check isn't done if there is not end/(due?) date. But I don't know whether the code applies to tasks.

In any case, with "show missed" set, the alarm should always show:
https://searchfox.org/comm-central/rev/25a5e99e1e75363df8b21c0257a56ce7d10f9b38/calendar/base/src/CalAlarmService.sys.mjs#500-504

Magnus, you worked on this code last? How is this meant to work and is there a bug somewhere?

Comment 8

[Francesco]

Maybe bug 1954358 matters here, since this was fixed for TB 139, the alleged first bad version.

Comment 9

[Mike]

(In reply to Francesco from comment #5)

...
Can someone give exact details to reproduce the problem on a freshly added task:
...

Please see my post at https://support.mozilla.org/en-US/questions/1511047?page=2#answer-1764095

Comment 10

[CL1]

OP here. TIme has passed since I opened my bug report in June 2025. In these last 3 months, I have seen an important distinction. When I create any original task that repeats (every day, or every week, or every month, etc.), my task appears in the reminder dialogue window on its first appointed time. If I use that task reminder window to delete the task, it deletes and appropriately I don't see it again. If instead I use that task reminder window to postpone the task (for another day or week, etc.), I never see the task again appear in the reminder dialogue window.

This is repeatable as I observe my tasks over days and weeks. Sorry the minimum task repeat choice is daily. Summary: a repeating task appears in the reminder dialogue window the first time, then never again after postponing it.

Comment 11

[Magnus Melin [:mkmelin]]

Attachment: Bug 1972904 - For show missed reminders, account for missing end dates and moved due dates. r=tobyp

Inspired by https://github.com/Betterbird/thunderbird-patches/blob/main/140/bugs/1988288-reminders-for-future-events.patch

Comment 12

[Francesco]

Does this also fix bug 1988288?

Comment 13

[Magnus Melin [:mkmelin]]

I think so. It looks at the event/task time (not the reminder time) to determine whether to show reminder anyway, which seems what you wanted.

Comment 14

[Francesco]

(In reply to Magnus Melin [:mkmelin] from comment #13)

I think so. It looks at the event/task time (not the reminder time) to determine whether to show reminder anyway, which seems what you wanted.

Thanks. I'm not the only TB user ;-) - I've just bundled four duplicates of people who all wanted the same. Whether the reminder shows should not depend on the reminder time, but on the time of the event itself since the application/computer might be closed at the time of the reminder. This most prominently applies to all-day events which were already treated specially.

Comment 15

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/comm-central/rev/d540e9e7da97
For show missed reminders, account for missing end dates and moved due dates. r=tobyp

Comment 16

[Magnus Melin [:mkmelin]]

Comment on attachment 9513205 [details]
Bug 1972904 - For show missed reminders, account for missing end dates and moved due dates. r=tobyp

Uplift Approval Request

• Please state case for uplift consideration and ensure bug severity is set: Broken funcionality
• User impact if declined: May miss reminders
• Is this code covered by automated tests?: No
• Has the fix been verified in Daily?: Yes
• Has the fix been verified in Beta?: No
• Needs manual test from QA?: No
• If yes, steps to reproduce:
• List of other uplifts needed: None
• Risk to taking this patch: Low
• Why is the change risky/not risky? (and alternatives if risky): Confined change.
• Does the fix cause any migrations to be skipped?: No
• String changes made/needed: none

Comment 17

[Corey Bryant]

Comment on attachment 9513205 [details]
Bug 1972904 - For show missed reminders, account for missing end dates and moved due dates. r=tobyp

[Triage Comment]
Approved for beta

Comment 18

[Daniel Darnell [:dandarnell]]

Thunderbird 144.0b2:
https://hg.mozilla.org/releases/comm-beta/rev/f4bae4e3da38

Comment 20

[Magnus Melin [:mkmelin]]

Comment on attachment 9513205 [details]
Bug 1972904 - For show missed reminders, account for missing end dates and moved due dates. r=tobyp

Uplift Approval Request

• Please state case for uplift consideration and ensure bug severity is set: Regression. Likely a bit annoying one with the right (wrong) data.
• User impact if declined: Per bug summary, but erroring out can have side effects like bug 1993220.
• Is this code covered by automated tests?: No
• Has the fix been verified in Daily?: Yes
• Has the fix been verified in Beta?: Yes
• Needs manual test from QA?: No
• If yes, steps to reproduce:
• List of other uplifts needed: None
• Risk to taking this patch: Low
• Why is the change risky/not risky? (and alternatives if risky): Confined change
• Does the fix cause any migrations to be skipped?: No
• String changes made/needed: none