hello, sync doesn't have a concept like a master device - all changes are synced across all devices and once they are synced the data will stay on the devices, even after you unlink them from your account. so in your case - when you have already transitioned the data successfully - you can either unlink your desktop from the sync account (through firefox > settings > sync) or close the whole account at https://account.services.mozilla.com/, since it doesn't really have a benefit when only one device is connected...

Very cool, and I have unlinked on the laptop, confirmed everythings still there. So just to be clear, now that I have a sync account setup, If I add new devices, I just need to pair them to the sync account, sync, and then unlink (if I choose not to have a true sync, but use it as a migration tool)?

yes, in principle this is correct - however the current sync accounts will be retired soon and replaced by a system that is working similar but will be easier to set-up initially (it will only ask for a email and a password and won't make use of the one-time pairing keys or the recovery key anymore): https://blog.mozilla.org/services/2014/02/07/a-better-firefox-sync/

the new sync won't be compatible with the current system and new accounts will have to be created, so i don't know if its worthwhile keeping your current account for this short period until firefox 29 is going to be released...

Good to know, with retirement will it reset my sync / effectively wipe my data or I will just the sync service no longer be available?

once the data has reached your device, it's not dependent on sync anymore, so this desn't affect your local data. i'm not entirely sure on how long the transition period will be, but at one point i suspect that the old sync servers will just be taken offline and encrypted data on there will be deleted.

See also:

• https://wiki.mozilla.org/User_Services/Sync/Relaunch

You guys rock, ty - all questions answered.