Batch notifications during active conversations

[kittykat]

Describe the bug

My Android app makes my phone buzz off the desk when there is an active conversation in a room.

To Reproduce

Steps to reproduce the behavior:

1. Lock phone
2. Have an active conversation happen in a room with noisy notifications.
3. Phone buzzes non-stop, draining battery a lot faster than it should (and it's very disruptive)

Expected behavior

If a user messages me or if there are multiple messages in quick succession in a room, the notifications should be batched and only the first one should be noisy. The notifications which come in quick succession after the first one should not trigger more noisy notifications and some time should pass before the next noisy notification from that chat.

Maybe notify for the first message and then not notify for the following 30 seconds if the messages are less than a second apart?

I believe Telegram batches notifications like this. Telegram notifications are broken in different and exciting ways.

See also element-hq/element-meta#360

Smartphone (please complete the following information):

• Device: Pixel 2
• OS: Android 11

Additional context

• App store, version 1.1.15 [40101152] (G-b2969)
• Homeserver: matrix.org

[ouchadam]

this seems like the enhancement version of #3774

if we don't need custom timing rules we could consider this done

what do you think @kittykat ?

[kittykat]

I can't reproduce right now to test because the notifications have stopped working for me altogether, but I don't think this needs to be a user configurable option. IMO, it's enough to have a sensible default.