How 1Password resolve edit conflict without sending unencrypted data to server?

Hi nawan​,

I asked my colleague ScottS1P​ about your questions to try and get a more detailed answer for you! Here's what he told me:

Every item in 1Password is versioned, and each version triggers an automatic sync to every connected device (offline devices also sync on unlock). Typically this means that conflicts are rare, but if there is a problem, it is resolved locally on the device with the conflict by keeping both the local and remote changes. 

Consider this hypothetical login item:

Title: Test item
Username: hello_world
Password: 1234
website: example.com
 

Two users have access to edit items in the vault with this item, and while offline, both make edits.

User 1:

Title: Test item
Username: hello_world
Password: 12345
website: example.com

User 2:

Title: Test item
Username: hello_world
Password: abcdef
website: example.com

The first change would apply normally when they next unlock and sync with 1Password. When the next user unlocks while online and becomes aware of the change, their device will change the item to persist both sets of changes. This is then synced to the server so everyone has all of the info.

Title: Test item
Username: hello_world
Password: abcdef
Password: 12345
website: example.com

After this, a user will have to notice the change, confirm which is correct, and edit the item to remove any extraneous or incorrect info. All of these revisions would be captured in the item and password history, so no data is lost.

Everything is encrypted before syncing to the server, and decrypted locally when syncing back down to a device, so it's easier to reason about how we handle the conflicts by thinking about the plain text on the device, but all of the end-to-end, zero-knowledge encryption is still happening in the background like always.

I hope this is helpful!