Key Backup is broken (for my account/client) with NO warning and NO remediation steps

[colemickens]

Steps to reproduce

1. I have no idea. Be me? On Element Web (same behavior on two different laptops)? Try to join Key Backup

Please see this 30 second demo for context: https://www.youtube.com/watch?v=mHDxBK4klss

Outcome

What did you expect?

• Joining Key Backup to work.
• Automatically, when I verified this session.

In lieu of it not working, it should guide me through how to fix it. And warn me that it didn't actually connect.

The entire UX of this page needs a lot of love, and I say that with ... love and concern and maybe some other emotions.

What happened instead?

1. There was NO warning that my clients were not participating in Key Backup. Ever, as far as I can tell

2. There was NO warning after attempting to join Key Backup, that I had still not joined Key Backup. If I weren't paying attention, this would have caused data loss, as I'm due to return a loaner laptop which was the only place those keys were stored until I manually backed them up.

3. There were no instructions on how to remediate "Failed to decrypt 8 sessions". I honestly have NO idea what that means, or how to fix it.

4. There is no clear way for me to "Fix" Key Backup.

Operating system

Linux, NixOS, 6.6.26

Browser information

Firefox - 126.0a1 - 20240412093252

URL for webapp

develop.element.io

Application version

Element version: 8ce46d3-react-6392759bec51-js-475f82c5ce94 Crypto version: Rust SDK 0.7.0 (61b175b), Vodozemac 0.5.1

Homeserver

matrix.org

Will you send logs?

Yes

[colemickens]

(I did the rageshake thing, it seemed successful! Hope y'all got it!)

[richvdh]

Duplicate of #26530, mostly.

The 8 failed sessions are corrupt in some way, likely due to a bug in another client, probably element-hq/element-meta#2338. Unfortunately there's not much more information we can give you here.