What it means
Signing out a Firefox connected service removes that device's Mozilla account connection. A device wipe or reset clears local data under the operating system's process. These actions solve different problems, especially when a laptop is being sold or has been lost.
A real-world example
An old laptop disappears from Connected Services after remote sign-out. Its local Firefox profile may still contain previously downloaded bookmarks or saved information until the machine is properly reset.
What to do
Use Connected Services to remove the stale connection, then reset a device you still own before transfer. For a missing device, secure account credentials and review exposure of local data.
The distinction that matters
Disabling Sync is also different from signing out of the Mozilla account. Mozilla's guidance explicitly separates these options. Remote sign-out should not be presented as proof that a thief's offline copy of data vanished.
Mozilla's connected-services controls Mozilla's Sync sign-out guidance
