Skip to content

MSC3768: Push rule action for in-app notifications #3768

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
wants to merge 4 commits into
base: main
Choose a base branch
from
Open

MSC3768: Push rule action for in-app notifications #3768

Changes from all commits
Commits
Show all changes
4 commits
Select commit Hold shift + click to select a range
1c33d23
Add in-app notification action proposal
Johennes Apr 8, 2022
cc735f0
Remove code formatting from headings to increase legibility
Johennes Apr 8, 2022
fe40800
Update proposals/3768-notify-in-app.md
Johennes Apr 8, 2022
d413236
Apply suggestions from code review
bnjbvr Aug 18, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
104 changes: 104 additions & 0 deletions proposals/3768-notify-in-app.md
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,104 @@
# MSC3768: Push rule action for in-app notifications

The [push rule] system is used in two different ways. Home servers
evaluate the rules on messages (which may be encrypted) and send *push*
notifications. Clients re-evaluate the rules locally on (decrypted)
messages and display *in-app* notifications -- most commonly in the form
of notification-count badges.

However, there is currently no way to stop sending push notifications
while still receiving in-app notifications. This is a critical feature
of "Do Not Disturb" modes where users want to stop being notified
*outside* their client but still see notifications *inside* their client
so that they can catch up on them after leaving "Do Not Disturb" mode.

The present proposal attempts to resolve this situation by introducing a
dedicated push rule action for in-app notifications without accompanying
push notifications.

## Proposal

A new push rule action `notify_in_app` is introduced.

- `notify_in_app` -- This causes each matching event to generate a
notification **without sending a push**. In particular, this means,
like `notify`, the server MUST consider the event when computing
`notification_count` and `highlight_count` in the `/sync` response.
Unlike `notify`, the server MAY skip forwarding the notification to
any of its pushers. Suppressing the push is OPTIONAL because clients
need to locally reapply push rules upon receiving push notifications
anyway due to E2EE. Clients MUST suppress push notifications that
resulted from `notify_in_app` but SHOULD display in-app notifications
just like for `notify`.

The existing `notify` action is changed to imply `notify_in_app`.

- `notify` -- This causes each matching event to generate a
notification. Implies `notify_in_app`.

No change to the existing default push rules is required. Servers can
treat `notify_in_app` exactly like `notify`, merely omitting the push,
while clients don't have to distinguish between the two actions at all.
This makes for a minimally invasive solution to the problem of
in-app-only notifications.

## Potential issues
Copy link
Contributor Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

(I'm not sure if it's documented but I believe we're encouraged to only comment on the diff / file to facilitate threading.)

@bnjbvr said:

What about backwards compat: is it specified somewhere (in the existing spec, as I couldn't find it here) how a client should behave in the presence of an unknown action type?

Assuming one's using the new notify-in-app action: the only way to have the badge count correctly updated would be for an app to run the sync in a background service, right? In that case, it sounds like an alternative could be that the app adds some kind of live event handler, and decides, based on pattern matching the event's content, to generate a local notification/increment the badge count. This wouldn't require a new action, while putting the onus of implementation on clients.

The implementation in the Matrix Rust SDK brings a new notification mode that's a bit hard to translate in layperson's words, for the end users: "notify me on mentions and keywords from pushes, but for every message notify me locally". This might be a UX problem very specific to the Matrix Rust SDK (as in, the shape of API it provides), but I'm afraid this overall complexifies the user experience, with a single benefit of having the server generating fewer pushes.

To wit, though: generating fewer pushes is a noble goal that may bring some super nice benefits, especially in the context of MSC4028.

Copy link
Contributor Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

What about backwards compat: is it specified somewhere (in the existing spec, as I couldn't find it here) how a client should behave in the presence of an unknown action type?

The only related reference I am aware of is the one about ignoring dont_notify and coalesce.

I think ignoring works somewhat reasonably well here, too. A client that doesn't support this proposal would treat ["notify_in_app"] like [] and not notify at all. This achieves the goal of not causing remote notifications albeit at the cost of not having any notifications in that client.

Alternatively, we could turn notify_in_app into a new tweak that can be specified together with notify. Ignoring would then make old clients notify normally with the cost being that the setting to only notify in-app would have no effect whatsoever in these clients.

Assuming one's using the new notify-in-app action: the only way to have the badge count correctly updated would be for an app to run the sync in a background service, right?

If the server uses notify_in_app to actually suppress pushes, then yes. We did conclude in https://github.com/matrix-org/matrix-spec-proposals/pull/3768/files#r2229026617, however, that the server could just push regardless because the client has to locally filter remote notifications anyway. In that case the client could still update app-icon badge counts without letting the notifications pop up.

In that case, it sounds like an alternative could be that the app adds some kind of live event handler, and decides, based on pattern matching the event's content, to generate a local notification/increment the badge count. This wouldn't require a new action, while putting the onus of implementation on clients.

I'm not sure I fully understand what you mean. Isn't this essentially the background /sync option?

The implementation in the Matrix Rust SDK brings a new notification mode that's a bit hard to translate in layperson's words, for the end users: "notify me on mentions and keywords from pushes, but for every message notify me locally". This might be a UX problem very specific to the Matrix Rust SDK (as in, the shape of API it provides), but I'm afraid this overall complexifies the user experience, with a single benefit of having the server generating fewer pushes.

This is true. I had chosen this as a first step because it's very easy to implement (same as the existing mentions & keywords mode but with a different action). UX-wise this might not be overly useful, however. I think the end goal should be to set a room to notify-in-app entirely. This is more complicated to manage though because it also involves tweaking the various override rules.

Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

(Oops, sorry for not starting a thread on the diff, and thanks for reproducing it here 👍)

I'm not sure I fully understand what you mean. Isn't this essentially the background /sync option?

I don't think that /sync needs to be involved, in this alternative; if the push notifications are still emitted by the server, it can be the client's responsibility to "lower" them into app-only notifications. If the server doesn't send the push notifications, indeed a background /sync is sufficient to achieve the same effect.

In both cases: if the suppression of a notification is the responsibility of a device, then we have another way of achieving the same outcome without this MSC. I wonder if this was also the question behind #3768 (comment).

So here's me thinking out loud about cost vs benefits, here:

  • the cost is mostly the implementation burden (clients + servers), maybe some extra weight in terms of explaining this new behavior in layperson's words so that it's easy to explain what this does.
  • one benefit would be that a server now doesn't have to send a push for each notification. For this to be valuable, it would likely have to be a default behavior (e.g. become a default push rule), for the economies of scale to kick in. In other words: it might not be as interesting if only a small fraction of the end users are using this new rule.
  • one other benefit is getting the synchronization of the suppression of push notifications across devices. However, I wonder if there are other, more lightweight ways to implement this preference synchronization (account data entry?).

(Of course this list doesn't pretend to be exhaustive, and maybe I'm missing the point of this MSC. Please, feel free to add other benefits/drawbacks here!)

Copy link
Contributor Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I don't think that /sync needs to be involved, in this alternative; if the push notifications are still emitted by the server, it can be the client's responsibility to "lower" them into app-only notifications. If the server doesn't send the push notifications, indeed a background /sync is sufficient to achieve the same effect.

Ok, I think we're saying the same then actually.

In both cases: if the suppression of a notification is the responsibility of a device, then we have another way of achieving the same outcome without this MSC.

It sounds like what you're suggesting is for a client to store some setting in an account data event and then use that setting when processing remote notifications to selectively suppress them. Such an event could look like this:

{
  "type": "some.client.in_app_notifications",
  "content": {
    "rooms": ["!asdf:matrix.org", ...]
  }
}

This seems viable but also somewhat equivalent to what this proposal already does. Push rules are stored in account data and clients use notify and notify_in_app to decide whether to suppress a remote notification or not.

The one benefit I can see is not having to fiddle with the notorious push rule system?

Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

The one benefit I can see is not having to fiddle with the notorious push rule system?

This is a huge benefit IMO 😁


None.

## Alternatives
Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I realise these 2 are newer, but it would be interesting to add references to #3881 and #3890 here. I seem to remember we added support for these to Element Classic (element-hq/element-ios#6815 / element-hq/element-ios#6798 – I'm failing to actually find them in the UI though) and I'm not sure I see the advantage of this approach over those.

Copy link
Contributor Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I think the difference is that the others are global while this one can work per room (though the push rule legwork to do so is not necessarily trivial).

Copy link
Contributor Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Suggested change
## Alternatives
## Alternatives
[MSC3881] and [MSC3890] solve a similar problem but can only disable
notifications globally and not per-room.

(I cannot apply this suggestion because I lost ownership of the branch.)

Copy link
Member

@pixlwave pixlwave Aug 20, 2025 •
edited
Loading

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Ahhhh, thanks for the clarification, I didn't see any mention of wanting to set per-room DnD in the intro so that didn't even cross my mind 🙃


[MSC3881] and [MSC3890] solve a similar problem but can only disable
notifications globally and not per-room.

Several attempts at fixing similar problems have been made in the past.
Most of these alternatives fell through because they separated unread
and notification counts. For the specific case of in-app-only
notifications, such a separation is not needed and only adds unnecessary
complexity.

For the sake of completeness, what follows is the result of an exercise
in archaeology:

### dont_push action

An experimental [Synapse PR] defined a `dont_push` action. While the
latter exhibits the same semantics as `notify_in_app`, its naming
disguises the fact that notifications are still being displayed in-app.
The PR was abandoned in favor of [MSC2625].

### MSC2625: Add `mark_unread` push rule action #2625

[MSC2625] went a step further by introducing a `mark_unread` action
together with an explicit `unread_count` next to the existing
`notification_count` and `highlight_count` in the `/sync` response. As
explained above, this kind of separation is not actually needed for
in-app-only notifications. [MSC2625], too, got abandoned, this time in
favor of [MSC2654].

### MSC2654: Unread counts

Finally, [MSC2654] went yet further and introduced a separate system for
computing unread counters without push rules. Again, the complexity
resulting from this separation is not actually required to support
in-app-only notifications.

## Security considerations

None.

## Unstable prefix

While this MSC is not considered stable, `notify_in_app` should be
referred to as `org.matrix.msc3768.notify_in_app`.

## Dependencies

None.

[push rule]: https://spec.matrix.org/v1.2/client-server-api/#push-rules
[Synapse PR]: https://github.com/matrix-org/synapse/pull/6061
[MSC2625]: https://github.com/matrix-org/matrix-spec-proposals/pull/2625
[MSC2654]: https://github.com/matrix-org/matrix-spec-proposals/pull/2654
[MSC3881]: https://github.com/matrix-org/matrix-spec-proposals/pull/3881
[MSC3890]: https://github.com/matrix-org/matrix-spec-proposals/pull/3890