Reminders are configured to trigger a notification after the event instead of before

[wout]

What Happened?

When creating a reminder for an event, the time span set to trigger a notification is applied after the event instead of before.

Here's an example of the time set in elementary OS calendar:

This is how Thunderbird reads it:

As well as the Fastmail calendar UI where it is actually hosted:

I've had this issue for ages, and I initially thought it was a timezone mixup. But now I can see it's a bug.

Steps to Reproduce

1. Create a new event in Calendar
2. Set a reminder for the event (e.g. 2 hours before)
3. Go to another app to see the reminder setting to verify how it's applied

Expected Behavior

Events should trigger before, just like the Calendar UI communicates it.

OS Version

7.x (Horus)

Software Version

Latest release (I have run all updates)

Log Output

No response

Hardware Info

[MrBrzoza]

This is very annoying. I almost missed two meetings recently because of it.

This happens in every calendar I use (Google, Nextloud).

Each entry, even though set to x minutes before, in the above calendars is set to x minutes after.