Repeated timeline, many read receipts

[timokoesters]

Steps to reproduce

Log in to a conduit account.
Accept a federated invite into a new room.

The problem seems to be related to the limited flag for syncs or the /messages endpoint.

Outcome

Your phone model

Operating system version

Application version and app store

Homeserver

conduit.rs

Will you send logs?

No

[BillCarsonFr]

So back pagination is like reloading the same page again
It's only when accepting a federated invite into a new room?

[timokoesters]

It's easy to reproduce when you are at the "start" of a timeline (/messages doesn't return any new events), but it seems to happen in other cases too.

[BillCarsonFr]

There is a difference between an empty pagination result on conduit.rs and synapse.

Synapse

{"chunk":[],"start":"t1-1339_71365_114_338_608_1_436_640_1","end":"t1-1339_71365_114_338_608_1_436_640_1"}

Conduit

{"start":"19057171","chunk":[]}

Looks like somehow android is expected the end to be set, wich as per spec shouldn't

end

If no further events are available (either because we have reached the start of the timeline, or because the user does not have permission to see any more events), this property is omitted from the response.

[BillCarsonFr]

Quikly confirmed by updating android code to use start for end when chunk is empty and it's working fine

[HarHarLinks]

I've hit something very similar on SchildiChat based on 1.4.4 with synapse 1.54.0.
I opened a room, clicked to jump to first unread, tried to scroll down from there but the timeline would repeat itself endlessly from there.

Expand to show a screenshot of the loop

I did rageshake this (to the schildi devs).

[MadLittleMods]

I reproduced a repeating never-ending timeline a lot when I had to use Element Android on a trip (matrix.org which is Synapse). Here is a rageshake, https://github.com/matrix-org/element-android-rageshakes/issues/35689. This was with normal messages, not just state events and read receipts.

[MrAureliusR]

This bit me when self-hosting a Conduit server. It's just an endless scroll of the same messages over and over, and duplicated read receipts.

.

[SpiritCroc]

I wonder if this issue will be fixed with 638e18e from #5878 .

That PR and some more experimental changes for timeline loops are already included in the latest SchildiChat beta (1.4.13.sc53-test1), if anybody is interested in testing it.

[MrAureliusR]

I wonder if this issue will be fixed with 638e18e from #5878 .

That PR and some more experimental changes for timeline loops are already included in the latest SchildiChat beta (1.4.13.sc53-test1), if anybody is interested in testing it.

Just downloaded SchildiChat on my Android device and joined the beta. After it updated to the beta version, signed into my homeserver -- exact same issue as with Element.

[SpiritCroc]

I wonder if this issue will be fixed with 638e18e from #5878 .
That PR and some more experimental changes for timeline loops are already included in the latest SchildiChat beta (1.4.13.sc53-test1), if anybody is interested in testing it.

Just downloaded SchildiChat on my Android device and joined the beta. After it updated to the beta version, signed into my homeserver -- exact same issue as with Element.

Sure you have the right version? (Note we distribute betas on our own fdroid server, google play betas are usually outdated)

[ganfra]

This also happens on synapse if you have a version > 1.6 (matrix-org/synapse#12903)
Related: #6312

[babolivier]

This also happens on synapse if you have a version > 1.6

For the paper trail and future digital archaeologists, the Synapse versions triggering this bug are > 1.61.0