Historic messages decrypt on cache reloading, but not before

[wrjlewis]

Steps to reproduce

Sign into a new instance of Element X
Verify your device
Open some chats with historic E2EE message, those messages can appear as UTDs
Clear EX cache in developer settings
All historic messages are now decrypted properly

Outcome

What did you expect?

Historic messages decrypt successfully, and are displayed as such, without having to cache reload.

What happened instead?

Historic messages that are shown as UTDs in the timeline seem stuck that way indefinitely. It could be that the keys are being downloaded or processed at the same time as a user trying to open the message, EX is unable to show the message and presents it as a UTD, and subsequently doesn't attempt to decrypt the message again in future.

Your phone model

iPhone 12 pro

Operating system version

MacOS and iOS

Application version

1.6.13

Homeserver

Synapse

Will you send logs?

No

[pixlwave]

This sounds like it might be similar to #3045 but viewed from a different perspective.

[wrjlewis]

This sounds like it might be similar to #3045 but viewed from a different perspective.

Yup sounds similar - ie EX caching the fact it's not immediately been able to decrypt the event

[ara4n]

Getting similar on EXA too: element-hq/element-x-android#3234

[richvdh]

Since this seems common to EXI and EXA, and likely a problem in the rust layer, I have pulled out a common issue to track fixing this in the rust layer: matrix-org/matrix-rust-sdk#3768

[wrjlewis]

Still seeing this, as are others I know running EX, consistently.
@neilisfragile ran into this on Friday on switchover to SSS which forces a logout / login.

[richvdh]

Please do send rageshakes for any observed UTDs. Our decisions for which UTD causes get fixed are pretty directly based on the number of rageshakes we see for those causes.

[neilisfragile]

Here is a rageshake, though I (and I think anyone) can consistently reproduce.
https://github.com/element-hq/element-x-ios-rageshakes/issues/2088

[ara4n]

i wonder if this is the same as #2417.

It might also be happening on EXA in element-hq/element-x-android#3382

[thibaultamartin]

Happening to me as well on Element X nightly, after turning "Force Native Sync" and logging out and back in. The suggested workaround to clear the cache fixes things. Happy to test again once there is a fix in EX

[pixlwave]

I saw the same thing on migrating my personal account to SSS and logged in/out multiple times wondering if cross-signing was broken. A force quit worked for me rather than clearing the cache.

[poljar]

As matrix-org/matrix-rust-sdk#3964 has been closed, this should be done, I'll leave this issue open until there's a EX-iOS release confirming this.

[pixlwave]

Ok nice, #3215 includes an SDK update with that PR.

[manuroe]

@pixlwave can you verify it is fixed in the EXI app?

[pixlwave]

I can confirm, this is working now:

backup.mp4