Device remains unverified after repeated successful verifications (`ConstraintError: Unable to add key to index 'by_info': at least one key does not satisfy the uniqueness requirements.`)

[jackrosenthal]

Steps to reproduce

1. Start at Verify this Device: After end of April 2026....
2. Click Continue.
3. Do the verification using QR code on Element Android. Verification is successful, green check mark received on both ends.

Outcome

What did you expect?

Device would be verified after successful verification.

What happened instead?

Device remains unverified. Popups to verify the device remain.

Operating system

Linux

Browser information

Google Chrome 145.0.7632.116 (Official Build) (64-bit)

URL for webapp

https://app.element.io

Application version

Element version: 1.12.14 Crypto version: Rust SDK 0.16.0 (1ac734e), Vodozemac 0.9.0

Homeserver

matrix.ohea.xyz, Synapse/1.150.0

Will you send logs?

Yes

[uhoreg]

Thank you for the report. From the logs that you submitted, it looks like there is some internal error that is causing the verification to fail. I'll take a look into it, but in the mean time, try verifying by comparing emoji, rather than by scanning a QR code.

[uhoreg]

Actually, looking at the code and the logs again, you may still run into the issue even when verifying with emoji. It looks like something weird has happened in your browser storage, so you may need to log out and log back in.

[uhoreg]

This is an issue in the Rust SDK, so I've created matrix-org/matrix-rust-sdk#6518 to track this.

[andybalaam]

Keeping this open to track the issue in element-web.

[richvdh]

This can happen if there was a previous attempt to verify, but for some reason we didn't receive the secrets back from the other device (likely because it didn't have them; cf element-hq/element-meta#2642).

I think this is an easy fix, as proposed by @uhoreg in matrix-org/matrix-rust-sdk#6518 (comment).