Key exchange Tartine<->Tartine is not starting

[estellecomment]

Reproduce :

• Open a new tartine client in a new clean browser.
• log in and refuse all dialogs for restoring keys. You now have a new client with no keys.
• Request keys to be able to decrypt messages.

Expected : all open clients display a key exchange dialog.
Obtained : tchap v2 displays a key exchange dialog, but tartine does not.

Notes :

• in existing Tartine client, the new session is listed in "Where you're signed in", under "Unverified devices".
• in new Tartine client, in Settings, Security, "Verify current session" does not offer key exchange between devices :
  
  Same screen in element offers the key exchange between devices :
  

[estellecomment]

Note : this may be because none of my sessions were verified. We have to figure out if this is common or not.

[jdauphant]

We may need cross-signing enabled

[odelcroi]

Closing this issue as it does not happen with cross signing disabled, feel free to reopen if it happens again