From ad61e4f6bef5f7eff138c0c45d451627efbbc235 Mon Sep 17 00:00:00 2001 From: Johannes Marbach Date: Tue, 16 Sep 2025 12:42:25 +0200 Subject: [PATCH 1/4] MSC4356: Recently used emoji Signed-off-by: Johannes Marbach --- proposals/4356-recent-emoji.md | 65 ++++++++++++++++++++++++++++++++++ 1 file changed, 65 insertions(+) create mode 100644 proposals/4356-recent-emoji.md diff --git a/proposals/4356-recent-emoji.md b/proposals/4356-recent-emoji.md new file mode 100644 index 00000000000..bc36440b642 --- /dev/null +++ b/proposals/4356-recent-emoji.md @@ -0,0 +1,65 @@ +# MSC4356: Recently used emoji + +Like other chat platforms, Matrix supports emoji as a way to visually express ideas or emotions. In +practice, most people use a limited set of emoji only. Since emoji are commonly used as a quick way +to react to something, it is desirable for clients to offer users shortcuts to their favorite emoji. +Some emoji picker libraries support this feature by locally tracking emoji usage. This doesn't work +well in a multi-device environment, however, because such history cannot easily be shared between +clients. + +This proposal introduces a way for clients to maintain a shared storage of recently used emoji to +enable emoji suggestions across clients. + +## Proposal + +A new global account data event `m.recent_emoji` is introduced. In `content`, it contains a single +property `recent_emoji` that is an array where each element is itself an array. The first element in +this nested array is the emoji, the second element is a counter for how often it was used. The outer +`recent_emoji` array is ordered descendingly by last usage time. + +``` json5 +{ + "type": "m.recent_emoji", + "content": { + "recent_emoji": [ + [ "😅", 7 ], // Most recently used, 7 times overall + [ "👍", 84 ], // Second most recently used, 84 times overall + ... + } +} +``` + +When an emoji is used in a message or an annotation, the sending client moves (or adds) it to the +beginning of the `recent_emoji` array and increments (or initializes) its counter. + +As new emoji are being used, clients SHOULD limit the length of the `recent_emoji` array by dropping +elements from the end. A RECOMMENDED maximum length is 100 emoji. + +Clients MAY freely customise the logic for generating recommendations from the stored emoji. As an +example, they could select the 24 first (= most recently used) emoji and stably sort them by their +counters (so that more recently used emoji are ordered first on ties). + +## Potential issues + +Clients could choose wildly different ways to generate recommendations from the shared storage +leading to significantly different UX across clients. + +## Alternatives + +Further metadata such as the concrete access time or the room could be tracked together with emoji. +It is unclear, however, if this would lead to materially better suggestions, however. + +## Security considerations + +This proposal doesn't mandate encrypting the `m.recent_emoji` account data event. Since emoji are +most commonly used in annotations which are not encrypted, servers could already track and abuse +this information today, however. + +## Unstable prefix + +While this MSC is not considered stable, `m.recent_emoji` should be referred to as +`io.element.recent_emoji`. + +## Dependencies + +None. From 6e1cf39a015d025a51ae95a987606ba0118a85aa Mon Sep 17 00:00:00 2001 From: Johannes Marbach Date: Wed, 17 Sep 2025 08:21:08 +0200 Subject: [PATCH 2/4] Add note about the absence of further counter reset mechanisms --- proposals/4356-recent-emoji.md | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/proposals/4356-recent-emoji.md b/proposals/4356-recent-emoji.md index bc36440b642..4206c3e0e6f 100644 --- a/proposals/4356-recent-emoji.md +++ b/proposals/4356-recent-emoji.md @@ -33,7 +33,9 @@ When an emoji is used in a message or an annotation, the sending client moves (o beginning of the `recent_emoji` array and increments (or initializes) its counter. As new emoji are being used, clients SHOULD limit the length of the `recent_emoji` array by dropping -elements from the end. A RECOMMENDED maximum length is 100 emoji. +elements from the end. A RECOMMENDED maximum length is 100 emoji. Apart from this, no other +mechanism for resetting counters is mandated. [RFC7159] suggests an upper boundary of 2^53-1 for +interoperable integers which seems sufficiently large for all practical purposes. Clients MAY freely customise the logic for generating recommendations from the stored emoji. As an example, they could select the 24 first (= most recently used) emoji and stably sort them by their @@ -63,3 +65,5 @@ While this MSC is not considered stable, `m.recent_emoji` should be referred to ## Dependencies None. + + [RFC7159]: https://datatracker.ietf.org/doc/html/rfc7159 From 1ff30d4b24cc1cac8a4f2ee1d0c5fdc32ecf6c46 Mon Sep 17 00:00:00 2001 From: Johannes Marbach Date: Wed, 17 Sep 2025 16:06:02 +0200 Subject: [PATCH 3/4] Make proposal compatible with MSC4027 Signed-off-by: Johannes Marbach --- proposals/4356-recent-emoji.md | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/proposals/4356-recent-emoji.md b/proposals/4356-recent-emoji.md index 4206c3e0e6f..7eaaae4e8f2 100644 --- a/proposals/4356-recent-emoji.md +++ b/proposals/4356-recent-emoji.md @@ -32,6 +32,11 @@ this nested array is the emoji, the second element is a counter for how often it When an emoji is used in a message or an annotation, the sending client moves (or adds) it to the beginning of the `recent_emoji` array and increments (or initializes) its counter. +When an image is sent as an inline image or in a reaction (using [MSC4027]), the `mxc://` URI of the +image MAY be used as the "emoji" in this event. Clients which do not support such use of images MUST +tolerate the existence of `mxc://` entries, e.g. by ignoring the entries when deciding what to +display to the user, while still preserving them when modifying the list. + As new emoji are being used, clients SHOULD limit the length of the `recent_emoji` array by dropping elements from the end. A RECOMMENDED maximum length is 100 emoji. Apart from this, no other mechanism for resetting counters is mandated. [RFC7159] suggests an upper boundary of 2^53-1 for @@ -66,4 +71,5 @@ While this MSC is not considered stable, `m.recent_emoji` should be referred to None. + [MSC4027]: https://github.com/matrix-org/matrix-spec-proposals/pull/4027 [RFC7159]: https://datatracker.ietf.org/doc/html/rfc7159 From 58d45ad44a7f8e6f4d1e63b7b03b314014ce5b56 Mon Sep 17 00:00:00 2001 From: Johannes Marbach Date: Wed, 17 Sep 2025 16:11:08 +0200 Subject: [PATCH 4/4] Specify explicit upper limit of 2^53-1 Signed-off-by: Johannes Marbach --- proposals/4356-recent-emoji.md | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/proposals/4356-recent-emoji.md b/proposals/4356-recent-emoji.md index 7eaaae4e8f2..0b5e9495d4b 100644 --- a/proposals/4356-recent-emoji.md +++ b/proposals/4356-recent-emoji.md @@ -14,8 +14,8 @@ enable emoji suggestions across clients. A new global account data event `m.recent_emoji` is introduced. In `content`, it contains a single property `recent_emoji` that is an array where each element is itself an array. The first element in -this nested array is the emoji, the second element is a counter for how often it was used. The outer -`recent_emoji` array is ordered descendingly by last usage time. +this nested array is the emoji, the second element is a counter (\<= 2^53-1) for how often it was +used. The outer `recent_emoji` array is ordered descendingly by last usage time. ``` json5 { @@ -39,8 +39,8 @@ display to the user, while still preserving them when modifying the list. As new emoji are being used, clients SHOULD limit the length of the `recent_emoji` array by dropping elements from the end. A RECOMMENDED maximum length is 100 emoji. Apart from this, no other -mechanism for resetting counters is mandated. [RFC7159] suggests an upper boundary of 2^53-1 for -interoperable integers which seems sufficiently large for all practical purposes. +mechanism for resetting counters is mandated as the upper boundary of 2^53-1 seems sufficiently +large for all practical purposes. Clients MAY freely customise the logic for generating recommendations from the stored emoji. As an example, they could select the 24 first (= most recently used) emoji and stably sort them by their @@ -72,4 +72,3 @@ While this MSC is not considered stable, `m.recent_emoji` should be referred to None. [MSC4027]: https://github.com/matrix-org/matrix-spec-proposals/pull/4027 - [RFC7159]: https://datatracker.ietf.org/doc/html/rfc7159