diff --git a/alt-tab-macos/logic/Spaces.swift b/alt-tab-macos/logic/Spaces.swift
index 05a31988..155d21a4 100644
--- a/alt-tab-macos/logic/Spaces.swift
+++ b/alt-tab-macos/logic/Spaces.swift
@@ -10,6 +10,9 @@ class Spaces {
     static func observeSpaceChanges() {
         NSWorkspace.shared.notificationCenter.addObserver(forName: NSWorkspace.activeSpaceDidChangeNotification, object: nil, queue: nil, using: { _ in
             updateCurrentSpace()
+            let app = App.shared as! App
+            guard app.appIsBeingUsed else { return }
+            app.reopenUi()
         })
     }
 
diff --git a/alt-tab-macos/logic/SystemPermissions.swift b/alt-tab-macos/logic/SystemPermissions.swift
index 6e716cae..5e9c715f 100644
--- a/alt-tab-macos/logic/SystemPermissions.swift
+++ b/alt-tab-macos/logic/SystemPermissions.swift
@@ -10,7 +10,7 @@ class SystemPermissions {
                     "Please authorize and re-launch.",
                     "See https://help.rescuetime.com/article/59-how-do-i-enable-accessibility-permissions-on-mac-osx",
                     separator: "\n")
-            NSApp.terminate(self)
+            App.shared.terminate(self)
         }
     }
 
@@ -22,7 +22,7 @@ class SystemPermissions {
                     "Please authorize and re-launch.",
                     "See https://dropshare.zendesk.com/hc/en-us/articles/360033453434-Enabling-Screen-Recording-Permission-on-macOS-Catalina-10-15-",
                     separator: "\n")
-            NSApp.terminate(self)
+            App.shared.terminate(self)
         }
     }
 }
diff --git a/alt-tab-macos/ui/App.swift b/alt-tab-macos/ui/App.swift
index 0132b66b..b42e44c4 100644
--- a/alt-tab-macos/ui/App.swift
+++ b/alt-tab-macos/ui/App.swift
@@ -100,6 +100,13 @@ class App: NSApplication, NSApplicationDelegate, NSWindowDelegate {
         }
     }
 
+    func reopenUi() {
+        thumbnailsPanel!.orderOut(nil)
+        Windows.refreshAllThumbnails()
+        refreshOpenUi()
+        thumbnailsPanel!.show()
+    }
+
     func refreshOpenUi() {
         guard appIsBeingUsed else { return }
         let currentScreen = Screen.preferred() // fix screen between steps since it could change (e.g. mouse moved to another screen)
diff --git a/alt-tab-macos/ui/PreferencesWindow.swift b/alt-tab-macos/ui/PreferencesWindow.swift
index 261290b0..bd7aa401 100644
--- a/alt-tab-macos/ui/PreferencesWindow.swift
+++ b/alt-tab-macos/ui/PreferencesWindow.swift
@@ -208,7 +208,7 @@ class PreferencesWindow: NSWindow, NSWindowDelegate {
                 throw NSError.make(domain: "Preferences", message: "Please enter a valid value for '" + key + "'")
             }
             try Preferences.updateAndValidateFromString(key, newValue)
-            (NSApp as! App).initPreferencesDependentComponents()
+            (App.shared as! App).initPreferencesDependentComponents()
             try Preferences.saveRawToDisk()
         } catch let error {
             debugPrint("PreferencesWindow: save: error", key, newValue, error)