This morning Firefox on my Macbook Pro doesn's remember any passwords. Sync-log indicates something is wrong (see below). Sync appears to be working on my Linux machine, so this problem is between the Mac and the sync-server. I have not changed my master-password recently. This is the most recent file in about:sync-log. 1523850866794 Sync.Service INFO Loading Weave 1.61.0 1523850866796 Sync.Engine.Clients DEBUG Engine constructed 1523850866798 Sync.Engine.Clients DEBUG Resetting clients last sync time 1523850880146 Sync.Engine.Clients DEBUG SyncEngine initialized: clients 1523850880166 Sync.Engine.Addons DEBUG Engine constructed 1523850888674 Sync.Engine.Addons DEBUG SyncEngine initialized: addons 1523850889030 Sync.Engine.Bookmarks DEBUG Engine constructed 1523850889086 Sync.Engine.Bookmarks DEBUG SyncEngine initialized: bookmarks 1523850889090 Sync.Engine.Forms DEBUG Engine constructed 1523850889124 Sync.Engine.Forms DEBUG SyncEngine initialized: forms 1523850889130 Sync.Engine.History DEBUG Engine constructed 1523850889140 Sync.Engine.History DEBUG SyncEngine initialized: history 1523850889146 Sync.Engine.Passwords DEBUG Engine constructed 1523850889160 Sync.Engine.Passwords DEBUG SyncEngine initialized: passwords 1523850889166 Sync.Engine.Prefs DEBUG Engine constructed 1523850889238 Sync.Engine.Prefs DEBUG SyncEngine initialized: prefs 1523850889248 Sync.Engine.Tabs DEBUG Engine constructed 1523850889288 Sync.Engine.Tabs DEBUG SyncEngine initialized: tabs 1523850889288 Sync.Engine.Tabs DEBUG Resetting tabs last sync time 1523850889292 Sync.Engine.Extension-Storage DEBUG Engine constructed 1523850889378 Sync.Engine.Extension-Storage DEBUG SyncEngine initialized: extension-storage 1523850889380 Sync.Service INFO Mozilla/5.0 (Macintosh; Intel Mac OS X 10.9; rv:59.0) Gecko/20100101 Firefox/59.0 1523850889386 Sync.Status DEBUG Status.service: success.status_ok => success.status_ok 1523850889392 Sync.Engine.History.Tracker INFO Adding Places observer. 1523850889722 Sync.Engine.Bookmarks.Tracker DEBUG migrateOldEntries: Missing bookmarks tracker file; skipping migration 1523850889722 Sync.AddonsReconciler INFO Registering as Add-on Manager listener. 1523850889724 Sync.AddonsReconciler DEBUG Adding change listener. 1523850890282 Sync.Status DEBUG Status.service: success.status_ok => success.status_ok 1523850890326 FirefoxAccounts TRACE not checking freshness of profile as it remains recent 1523850895512 Sync.SyncScheduler DEBUG Next sync in 3600000 ms. (why=schedule) 1523851052274 Sync.Status DEBUG Status.service: success.status_ok => success.status_ok 1523851052274 Sync.SyncScheduler DEBUG Next sync in 3442726 ms. (why=startup) 1523854461372 Sync.Service DEBUG User-Agent: Firefox/59.0.2 (Intel Mac OS X 10.9) FxSync/1.61.0.20180323154952.desktop 1523854461372 Sync.Service INFO Starting sync at 2018-04-16 07:54:21 in browser session hi-y2YpvHTvy 1523854461372 Sync.Service DEBUG In sync: should login. 1523854461372 Sync.Service INFO Logging in the user. 1523854461374 Sync.BrowserIDManager INFO Waiting for user to be verified. 1523854461376 FirefoxAccounts DEBUG already verified 1523854461376 Sync.BrowserIDManager INFO Starting fetch for key bundle. 1523854461376 Sync.BrowserIDManager INFO Unable to fetch keys (master-password locked?), so aborting token fetch 1523854461376 Sync.BrowserIDManager INFO Background fetch for key bundle done 1523854461376 Sync.Status DEBUG Status.login: success.login => success.login 1523854461376 Sync.Status DEBUG Status.service: success.status_ok => success.status_ok 1523854461376 Sync.Status DEBUG Status.service: success.status_ok => success.status_ok 1523854461376 Sync.Service INFO User logged in successfully - verifying login. 1523854461382 Sync.BrowserIDManager DEBUG unlockAndVerifyAuthState re-fetched credentials and is returning: error.login.reason.account 1523854461382 Sync.Service DEBUG Fetching unlocked auth state returned error.login.reason.account 1523854461382 Sync.Status DEBUG Status.login: success.login => error.login.reason.account 1523854461382 Sync.Status DEBUG Status.service: success.status_ok => error.login.failed 1523854461382 Sync.ErrorHandler ERROR Sync encountered a login error 1523854461382 Sync.SyncScheduler DEBUG Clearing sync triggers and the global score. 1523854461388 Sync.Service DEBUG Exception calling WrappedLock: Error: Login failed: error.login.reason.account (resource://services-sync/service.js:845:15) JS Stack trace: [email protected]:845:15 1523854461388 Sync.Service DEBUG Not syncing: login returned false. 1523854461390 Sync.ErrorHandler DEBUG Addons installed: 4 1523854461390 Sync.ErrorHandler DEBUG - Firefox Multi-Account Containers, version 6.0.0, id @testpilot-containers 1523854461392 Sync.ErrorHandler DEBUG - Google Analytics Opt-out Add-on (by Google), version 1.0.7, id {6d96bb5e-1175-4ebf-8ab5-5f56f1c79f65} 1523854461392 Sync.ErrorHandler DEBUG - Disconnect, version 5.18.21, id [email protected] 1523854461392 Sync.ErrorHandler DEBUG - Privacy Badger, version 2018.4.10, id jid1-MnnxcxisBPnSXQ-eff@jetpack