diff --git a/Sources/AppBundle/tree/frozen/closedWindowsCache.swift b/Sources/AppBundle/tree/frozen/closedWindowsCache.swift
index 323f0ceb..97af43d3 100644
--- a/Sources/AppBundle/tree/frozen/closedWindowsCache.swift
+++ b/Sources/AppBundle/tree/frozen/closedWindowsCache.swift
@@ -1,5 +1,4 @@
 import AppKit
-import Common
 
 /// First line of defence against lock screen
 ///
@@ -45,7 +44,6 @@ func cacheClosedWindowIfNeeded(window: Window) {
         workspaces: Workspace.all.map { FrozenWorkspace($0) },
         monitors: monitors.map(FrozenMonitor.init)
     )
-    check(closedWindowsCache.windowIds.contains(window.windowId))
 }
 
 func restoreClosedWindowsCacheIfNeeded(newlyDetectedWindow: Window) -> Bool {