diff --git a/src/logic/Appearance.swift b/src/logic/Appearance.swift
index 3558f0d1..0052897f 100644
--- a/src/logic/Appearance.swift
+++ b/src/logic/Appearance.swift
@@ -55,15 +55,14 @@ class Appearance {
     }
 
     private static func updateSize() {
-        let screen = NSScreen.preferred()
-        let isHorizontalScreen = screen.isHorizontal()
-        maxWidthOnScreen = AppearanceTestable.comfortableWidth(screen.physicalSize().map { $0.width })
+        let isHorizontalScreen = NSScreen.preferred.isHorizontal()
+        maxWidthOnScreen = AppearanceTestable.comfortableWidth(NSScreen.preferred.physicalSize().map { $0.width })
         if currentStyle == .appIcons {
             appIconsSize()
         } else if currentStyle == .titles {
             titlesSize(isHorizontalScreen)
         } else {
-            thumbnailsSize(isHorizontalScreen, screen)
+            thumbnailsSize(isHorizontalScreen)
         }
     }
 
@@ -75,7 +74,7 @@ class Appearance {
         }
     }
 
-    private static func thumbnailsSize(_ isHorizontalScreen: Bool, _ screen: NSScreen) {
+    private static func thumbnailsSize(_ isHorizontalScreen: Bool) {
         hideThumbnails = false
         windowPadding = 18
         cellCornerRadius = 10
@@ -95,7 +94,7 @@ class Appearance {
                 iconSize = 32
                 fontHeight = 16
         }
-        let thumbnailsPanelRatio = (screen.frame.width * maxWidthOnScreen) / (screen.frame.height * maxHeightOnScreen)
+        let thumbnailsPanelRatio = (NSScreen.preferred.frame.width * maxWidthOnScreen) / (NSScreen.preferred.frame.height * maxHeightOnScreen)
         (windowMinWidthInRow, windowMaxWidthInRow) = AppearanceTestable.goodValuesForThumbnailsWidthMinMax(thumbnailsPanelRatio, rowsCount)
         if currentVisibility == .highest {
             edgeInsetsSize = 10
diff --git a/src/logic/NSScreen.swift b/src/logic/NSScreen.swift
index 87956fea..ea35ca24 100644
--- a/src/logic/NSScreen.swift
+++ b/src/logic/NSScreen.swift
@@ -1,6 +1,45 @@
 import Cocoa
 
 extension NSScreen {
+    static var preferred: NSScreen = detectPreferred() ?? NSScreen.screens.first!
+
+    static func updatePreferred() {
+        preferred = detectPreferred() ?? NSScreen.screens.first!
+    }
+
+    private static func detectPreferred() -> NSScreen? {
+        switch Preferences.showOnScreen {
+            case .includingMouse: return withMouse()
+            case .active: return NSScreen.active()
+            case .includingMenubar: return NSScreen.screens.first
+        }
+    }
+
+    /// NSScreen.main docs are incorrect. It stopped returning the screen with the key window in macOS 10.9
+    /// see https://stackoverflow.com/a/56268826/2249756
+    /// There are a few cases where .main doesn't return the screen with the key window:
+    ///   * if the active screen shows a fullscreen app, it always returns screens[0]
+    ///   * if NSScreen.screensHaveSeparateSpaces == false, and key window is on another screen than screens[0], it still returns screens[0]
+    /// we find the screen with the key window ourselves manually
+    static func active() -> NSScreen? {
+        if let app = Applications.find(NSWorkspace.shared.frontmostApplication?.processIdentifier) {
+            if let focusedWindow = app.focusedWindow {
+                return NSScreen.screens.first { focusedWindow.isOnScreen($0) }
+            }
+            return NSScreen.withActiveMenubar()
+        }
+        return nil
+    }
+
+    /// there is only 1 active menubar. Other screens will show their menubar dimmed
+    static func withActiveMenubar() -> NSScreen? {
+        return NSScreen.screens.first { CGSCopyActiveMenuBarDisplayIdentifier(CGS_CONNECTION) == $0.uuid() }
+    }
+
+    static func withMouse() -> NSScreen? {
+        return NSScreen.screens.first { NSMouseInRect(NSEvent.mouseLocation, $0.frame, false) }
+    }
+
     func ratio() -> CGFloat {
         return frame.width / frame.height
     }
@@ -41,43 +80,6 @@ extension NSScreen {
         return nil
     }
 
-    static func preferred() -> NSScreen {
-        preferred_() ?? NSScreen.screens.first!
-    }
-
-    private static func preferred_() -> NSScreen? {
-        switch Preferences.showOnScreen {
-            case .includingMouse: return withMouse()
-            case .active: return NSScreen.active()
-            case .includingMenubar: return NSScreen.screens.first
-        }
-    }
-
-    /// NSScreen.main docs are incorrect. It stopped returning the screen with the key window in macOS 10.9
-    /// see https://stackoverflow.com/a/56268826/2249756
-    /// There are a few cases where .main doesn't return the screen with the key window:
-    ///   * if the active screen shows a fullscreen app, it always returns screens[0]
-    ///   * if NSScreen.screensHaveSeparateSpaces == false, and key window is on another screen than screens[0], it still returns screens[0]
-    /// we find the screen with the key window ourselves manually
-    static func active() -> NSScreen? {
-        if let app = Applications.find(NSWorkspace.shared.frontmostApplication?.processIdentifier) {
-            if let focusedWindow = app.focusedWindow {
-                return NSScreen.screens.first { focusedWindow.isOnScreen($0) }
-            }
-            return NSScreen.withActiveMenubar()
-        }
-        return nil
-    }
-
-    // there is only 1 active menubar. Other screens will show their menubar dimmed
-    static func withActiveMenubar() -> NSScreen? {
-        return NSScreen.screens.first { CGSCopyActiveMenuBarDisplayIdentifier(CGS_CONNECTION) == $0.uuid() }
-    }
-
-    static func withMouse() -> NSScreen? {
-        return NSScreen.screens.first { NSMouseInRect(NSEvent.mouseLocation, $0.frame, false) }
-    }
-
     func repositionPanel(_ window: NSWindow) {
         let screenFrame = visibleFrame
         let panelFrame = window.frame
diff --git a/src/logic/Window.swift b/src/logic/Window.swift
index f3186af1..eea22998 100644
--- a/src/logic/Window.swift
+++ b/src/logic/Window.swift
@@ -7,6 +7,7 @@ class Window {
     var creationOrder = Int.zero
     var title: String!
     var thumbnail: NSImage?
+    var thumbnailFullSize: NSSize?
     var icon: NSImage? { get { application.icon } }
     var shouldShowTheUser = true
     var isTabbed: Bool = false
@@ -98,12 +99,13 @@ class Window {
 
     func refreshThumbnail(_ screenshot: NSImage?) {
         thumbnail = screenshot
+        thumbnailFullSize = screenshot?.size
         if App.app.appIsBeingUsed && shouldShowTheUser {
             if let index = (Windows.list.firstIndex { $0.cgWindowId == cgWindowId }) {
                 let view = ThumbnailsView.recycledViews[index]
                 if !view.thumbnail.isHidden {
                     view.thumbnail.image = thumbnail
-                    let thumbnailSize = ThumbnailView.thumbnailSize(thumbnail, NSScreen.preferred(), false)
+                    let thumbnailSize = ThumbnailView.thumbnailSize(thumbnail, false)
                     view.thumbnail.image?.size = thumbnailSize
                     view.thumbnail.frame.size = thumbnailSize
                 }
diff --git a/src/logic/Windows.swift b/src/logic/Windows.swift
index 3a8aa606..8745786d 100644
--- a/src/logic/Windows.swift
+++ b/src/logic/Windows.swift
@@ -262,7 +262,7 @@ class Windows {
         }
     }
 
-    static func updatesBeforeShowing(_ screen: NSScreen) -> Bool {
+    static func updatesBeforeShowing() -> Bool {
         if list.count == 0 || MissionControl.state() == .showAllWindows || MissionControl.state() == .showFrontWindows { return false }
         // TODO: find a way to update space info when spaces are changed, instead of on every trigger
         // workaround: when Preferences > Mission Control > "Displays have separate Spaces" is unchecked,
@@ -275,9 +275,9 @@ class Windows {
             // TODO: can the CGS call inside detectTabbedWindows introduce latency when WindowServer is busy?
             detectTabbedWindows(window, cgsWindowIds, visibleCgsWindowIds)
             updatesWindowSpace(window)
-            refreshIfWindowShouldBeShownToTheUser(window, screen)
+            refreshIfWindowShouldBeShownToTheUser(window)
         }
-        refreshWhichWindowsToShowTheUser(screen)
+        refreshWhichWindowsToShowTheUser()
         sort()
         if (!list.contains { $0.shouldShowTheUser }) { return false }
         return true
@@ -337,7 +337,7 @@ class Windows {
         }
     }
 
-    static func refreshWhichWindowsToShowTheUser(_ screen: NSScreen) {
+    static func refreshWhichWindowsToShowTheUser() {
         if Preferences.onlyShowApplications() {
             // Group windows by application and select the optimal main window
             let windowsGroupedByApp = Dictionary(grouping: list) { $0.application.pid }
@@ -353,7 +353,7 @@ class Windows {
         }
     }
 
-    private static func refreshIfWindowShouldBeShownToTheUser(_ window: Window, _ screen: NSScreen) {
+    private static func refreshIfWindowShouldBeShownToTheUser(_ window: Window) {
         window.shouldShowTheUser =
             !(window.application.runningApplication.bundleIdentifier.flatMap { id in
                 Preferences.blacklist.contains {
@@ -368,7 +368,7 @@ class Windows {
                 !(!(Preferences.showFullscreenWindows[App.app.shortcutIndex] != .hide) && window.isFullscreen) &&
                 !(!(Preferences.showMinimizedWindows[App.app.shortcutIndex] != .hide) && window.isMinimized) &&
                 !(Preferences.spacesToShow[App.app.shortcutIndex] == .visible && !Spaces.visibleSpaces.contains(window.spaceId)) &&
-                !(Preferences.screensToShow[App.app.shortcutIndex] == .showingAltTab && !window.isOnScreen(screen)) &&
+                !(Preferences.screensToShow[App.app.shortcutIndex] == .showingAltTab && !window.isOnScreen(NSScreen.preferred)) &&
                 (Preferences.showTabsAsWindows || !window.isTabbed))
     }
 
diff --git a/src/ui/App.swift b/src/ui/App.swift
index 0573f42b..4fa2469a 100644
--- a/src/ui/App.swift
+++ b/src/ui/App.swift
@@ -145,7 +145,8 @@ class App: AppCenterApplication {
 
     func showSecondaryWindow(_ window: NSWindow?) {
         if let window = window {
-            NSScreen.preferred().repositionPanel(window)
+            NSScreen.updatePreferred()
+            NSScreen.preferred.repositionPanel(window)
             App.shared.activate(ignoringOtherApps: true)
             window.makeKeyAndOrderFront(nil)
             // Use the center function to continue to center, the `repositionPanel` function cannot center, it may be a system bug
@@ -201,19 +202,19 @@ class App: AppCenterApplication {
             return
         }
         guard appIsBeingUsed else { return }
-        let currentScreen = NSScreen.preferred() // fix screen between steps since it could change (e.g. mouse moved to another screen)
         if !skipUpdatesBeforeShowing {
-            if !Windows.updatesBeforeShowing(currentScreen) { hideUi(); return }
+            if !Windows.updatesBeforeShowing() { hideUi(); return }
         }
         guard appIsBeingUsed else { return }
         Windows.updateFocusedWindowIndex()
         guard appIsBeingUsed else { return }
-        thumbnailsPanel.thumbnailsView.updateItemsAndLayout(currentScreen)
+        print("updateItemsAndLayout")
+        thumbnailsPanel.thumbnailsView.updateItemsAndLayout()
         guard appIsBeingUsed else { return }
         thumbnailsPanel.setContentSize(thumbnailsPanel.thumbnailsView.frame.size)
         thumbnailsPanel.display()
         guard appIsBeingUsed else { return }
-        currentScreen.repositionPanel(thumbnailsPanel)
+        NSScreen.preferred.repositionPanel(thumbnailsPanel)
         guard appIsBeingUsed else { return }
         Windows.voiceOverWindow() // at this point ThumbnailViews are assigned to the window, and ready
         guard appIsBeingUsed else { return }
@@ -232,16 +233,16 @@ class App: AppCenterApplication {
             }
             isFirstSummon = false
             self.shortcutIndex = shortcutIndex
-            let screen = NSScreen.preferred()
-            if !Windows.updatesBeforeShowing(screen) { hideUi(); return }
+            NSScreen.updatePreferred()
+            if !Windows.updatesBeforeShowing() { hideUi(); return }
             Windows.setInitialFocusedAndHoveredWindowIndex()
             if Preferences.windowDisplayDelay == DispatchTimeInterval.milliseconds(0) {
-                buildUiAndShowPanel(screen)
+                buildUiAndShowPanel()
             } else {
                 delayedDisplayScheduled += 1
                 DispatchQueue.main.asyncAfter(deadline: DispatchTime.now() + Preferences.windowDisplayDelay) { () -> () in
                     if self.delayedDisplayScheduled == 1 {
-                        self.buildUiAndShowPanel(screen)
+                        self.buildUiAndShowPanel()
                     }
                     self.delayedDisplayScheduled -= 1
                 }
@@ -252,7 +253,7 @@ class App: AppCenterApplication {
         }
     }
 
-    func buildUiAndShowPanel(_ screen: NSScreen = NSScreen.preferred()) {
+    func buildUiAndShowPanel() {
         guard appIsBeingUsed else { return }
         Appearance.update()
         guard appIsBeingUsed else { return }
@@ -299,6 +300,7 @@ extension App: NSApplicationDelegate {
         SystemPermissions.ensurePermissionsAreGranted { [weak self] in
             guard let self = self else { return }
             BackgroundWork.start()
+            NSScreen.updatePreferred()
             Appearance.update()
             Menubar.initialize()
             self.loadMainMenuXib()
diff --git a/src/ui/main-window/ThumbnailView.swift b/src/ui/main-window/ThumbnailView.swift
index dd3cbea2..3c89755f 100644
--- a/src/ui/main-window/ThumbnailView.swift
+++ b/src/ui/main-window/ThumbnailView.swift
@@ -95,11 +95,11 @@ class ThumbnailView: FlippedView {
         observeDragAndDrop()
     }
 
-    func updateRecycledCellWithNewContent(_ element: Window, _ index: Int, _ newHeight: CGFloat, _ screen: NSScreen) {
+    func updateRecycledCellWithNewContent(_ element: Window, _ index: Int, _ newHeight: CGFloat) {
         window_ = element
-        updateValues(element, index, newHeight, screen)
-        updateSizes(newHeight, screen)
-        updatePositions(newHeight, screen)
+        updateValues(element, index, newHeight)
+        updateSizes(newHeight)
+        updatePositions(newHeight)
         label.toolTip = label.cell!.cellSize.width >= label.frame.size.width ? label.stringValue : nil
     }
 
@@ -298,7 +298,36 @@ class ThumbnailView: FlippedView {
         view.label.toolTip = view.label.cell!.cellSize.width >= view.label.frame.size.width ? view.label.stringValue : nil
     }
 
-    private func updateValues(_ element: Window, _ index: Int, _ newHeight: CGFloat, _ screen: NSScreen) {
+    private func updateThumbnail(_ element: Window) {
+        // we need to reset the original size, otherwise it may be too small and not get resized
+        // this can happen when switching from one screen to another for example
+        if let screenshot = element.thumbnail, let thumbnailFullSize = element.thumbnailFullSize {
+            screenshot.size = thumbnailFullSize
+        }
+        if !thumbnail.isHidden && thumbnail != element.thumbnail {
+            if let screenshot = element.thumbnail {
+                thumbnail.image = screenshot
+            } else if let appIconFallback = element.icon {
+                // if no thumbnail, show appIcon instead
+                // .icon is always 32x32 by default. We scale it so it can be "thumbnail-ed" down
+                appIconFallback.size = NSSize(width: 1024, height: 1024)
+                thumbnail.image = appIconFallback
+            }
+            // for Accessibility > "speak items under the pointer"
+            thumbnail.setAccessibilityLabel(element.title)
+        }
+    }
+
+    private func updateAppIcon(_ element: Window, _ title: String) -> Bool {
+        let appIconChanged = appIcon.image != element.icon
+        if appIconChanged {
+            appIcon.image = element.icon
+            appIcon.setAccessibilityLabel(title)
+        }
+        return appIconChanged
+    }
+
+    private func updateValues(_ element: Window, _ index: Int, _ newHeight: CGFloat) {
         assignIfDifferent(&thumbnail.isHidden, Appearance.hideThumbnails || element.isWindowlessApp)
         assignIfDifferent(&windowlessIcon.isHidden, !element.isWindowlessApp || Appearance.hideThumbnails)
         assignIfDifferent(&windowlessAppIndicator.isHidden, !element.isWindowlessApp)
@@ -310,11 +339,7 @@ class ThumbnailView: FlippedView {
                 NSScreen.screens.count < 2 || Preferences.screensToShow[App.app.shortcutIndex] == .showingAltTab
             )
         ))
-        if !thumbnail.isHidden {
-            thumbnail.image = element.thumbnail
-            // for Accessibility > "speak items under the pointer"
-            thumbnail.setAccessibilityLabel(element.title)
-        }
+        updateThumbnail(element)
         let title = getAppOrAndWindowTitle()
         let labelChanged = label.stringValue != title
         if labelChanged {
@@ -331,11 +356,7 @@ class ThumbnailView: FlippedView {
                 spaceIcon.toolTip = String(format: NSLocalizedString("Window is on Space %d", comment: ""), element.spaceIndex)
             }
         }
-        let appIconChanged = appIcon.image != element.icon
-        if appIconChanged {
-            appIcon.image = element.icon
-            appIcon.setAccessibilityLabel(title)
-        }
+        let appIconChanged = updateAppIcon(element, title)
         let dockLabelChanged = updateDockLabelIcon(element.dockLabel)
         if appIconChanged || dockLabelChanged {
             setAccessibilityHelp(getAccessibilityHelp(element.application.runningApplication.localizedName, element.dockLabel))
@@ -349,19 +370,19 @@ class ThumbnailView: FlippedView {
         mouseMovedCallback = { () -> Void in Windows.updateFocusedAndHoveredWindowIndex(index, true) }
     }
 
-    private func updateSizes(_ newHeight: CGFloat, _ screen: NSScreen) {
+    private func updateSizes(_ newHeight: CGFloat) {
         if Preferences.appearanceStyle == .thumbnails {
             if !thumbnail.isHidden {
-                let thumbnailSize = ThumbnailView.thumbnailSize(thumbnail.image, screen, false)
+                let thumbnailSize = ThumbnailView.thumbnailSize(thumbnail.image, false)
                 thumbnail.setSize(thumbnailSize)
             }
             if !windowlessIcon.isHidden {
-                let windowlessIconSize = ThumbnailView.thumbnailSize(windowlessIcon.image, screen, true)
+                let windowlessIconSize = ThumbnailView.thumbnailSize(windowlessIcon.image, true)
                 windowlessIcon.setSize(windowlessIconSize)
             }
         }
-        setFrameWidthHeight(screen, newHeight)
-        let appIconSize = ThumbnailView.iconSize(screen)
+        setFrameWidthHeight(newHeight)
+        let appIconSize = ThumbnailView.iconSize()
         appIcon.setSize(appIconSize)
         if Preferences.appearanceStyle == .appIcons {
             vStackView.frame.size = NSSize(width: frame.width, height: appIcon.frame.height + Appearance.edgeInsetsSize * 2)
@@ -378,7 +399,7 @@ class ThumbnailView: FlippedView {
         }
     }
 
-    private func updatePositions(_ newHeight: CGFloat, _ screen: NSScreen) {
+    private func updatePositions(_ newHeight: CGFloat) {
         hStackView.frame.origin = NSPoint(x: Appearance.edgeInsetsSize, y: Appearance.edgeInsetsSize)
         if Preferences.appearanceStyle != .appIcons {
             appIcon.frame.origin.x = App.shared.userInterfaceLayoutDirection == .leftToRight
@@ -426,7 +447,7 @@ class ThumbnailView: FlippedView {
             windowlessAppIndicator.frame.origin.y = windowlessAppIndicator.superview!.frame.height - windowlessAppIndicator.frame.height
         }
         if !dockLabelIcon.isHidden {
-            let iconSize = ThumbnailView.iconSize(screen)
+            let iconSize = ThumbnailView.iconSize()
             dockLabelIcon.frame.origin.x = ((iconSize.width * 0.8) - (dockLabelIcon.fittingSize.width / 2)).rounded()
             dockLabelIcon.frame.origin.y = ((iconSize.height * 0.8) - (dockLabelIcon.fittingSize.height / 2)).rounded()
                 - (Preferences.appearanceSize == .small ? 2 : 0)
@@ -449,18 +470,18 @@ class ThumbnailView: FlippedView {
         return windowTitle ?? ""
     }
 
-    private func setFrameWidthHeight(_ screen: NSScreen, _ newHeight: CGFloat) {
+    private func setFrameWidthHeight(_ newHeight: CGFloat) {
         var contentWidth = CGFloat(0)
         if Preferences.appearanceStyle == .thumbnails {
             // Preferred to the width of the image, and the minimum width may be set to be large.
             contentWidth = (!windowlessIcon.isHidden ? windowlessIcon : thumbnail).frame.size.width
         } else if Preferences.appearanceStyle == .titles {
-            contentWidth = ThumbnailView.maxThumbnailWidth(screen) - Appearance.edgeInsetsSize * 2
+            contentWidth = ThumbnailView.maxThumbnailWidth() - Appearance.edgeInsetsSize * 2
         } else {
             contentWidth = Appearance.iconSize
         }
         let frameWidth = (contentWidth + Appearance.edgeInsetsSize * 2).rounded()
-        let widthMin = ThumbnailView.minThumbnailWidth(screen)
+        let widthMin = ThumbnailView.minThumbnailWidth()
         let width = max(frameWidth, widthMin).rounded()
         assignIfDifferent(&frame.size.width, width)
         assignIfDifferent(&frame.size.height, newHeight)
@@ -489,7 +510,7 @@ class ThumbnailView: FlippedView {
     }
 
     static func dockLabelLabelSize() -> CGFloat {
-        let size = (ThumbnailView.iconSize(NSScreen.preferred()).width * 0.43).rounded()
+        let size = (ThumbnailView.iconSize().width * 0.43).rounded()
         // label should have a minimum size for readability
         return max(size, 13)
     }
@@ -505,33 +526,28 @@ class ThumbnailView: FlippedView {
         return shadow
     }
 
-    static func maxThumbnailWidth(_ screen: NSScreen) -> CGFloat {
-        return ThumbnailsPanel.maxThumbnailsWidth(screen) * Appearance.windowMaxWidthInRow - Appearance.interCellPadding * 2
+    static func maxThumbnailWidth() -> CGFloat {
+        return ThumbnailsPanel.maxThumbnailsWidth() * Appearance.windowMaxWidthInRow - Appearance.interCellPadding * 2
     }
 
-    static func minThumbnailWidth(_ screen: NSScreen) -> CGFloat {
-        return ThumbnailsPanel.maxThumbnailsWidth(screen) * Appearance.windowMinWidthInRow - Appearance.interCellPadding * 2
+    static func minThumbnailWidth() -> CGFloat {
+        return ThumbnailsPanel.maxThumbnailsWidth() * Appearance.windowMinWidthInRow - Appearance.interCellPadding * 2
     }
 
     /// The maximum height that a thumbnail can be drawn
-    ///
     /// maxThumbnailsHeight = maxThumbnailHeight * rowCount + interCellPadding * (rowCount - 1)
-    ///
     /// maxThumbnailHeight = (maxThumbnailsHeight - interCellPadding * (rowCount - 1)) / rowCount
-    ///
-    /// - Parameter screen:
-    /// - Returns:
-    static func maxThumbnailHeight(_ screen: NSScreen) -> CGFloat {
-        return (ThumbnailsPanel.maxThumbnailsHeight(screen) - Appearance.interCellPadding) / Appearance.rowsCount - Appearance.interCellPadding
+    static func maxThumbnailHeight() -> CGFloat {
+        return ((ThumbnailsPanel.maxThumbnailsHeight() - Appearance.interCellPadding) / Appearance.rowsCount - Appearance.interCellPadding).rounded()
     }
 
-    static func thumbnailSize(_ image: NSImage?, _ screen: NSScreen, _ isWindowlessApp: Bool) -> NSSize {
+    static func thumbnailSize(_ image: NSImage?, _ isWindowlessApp: Bool) -> NSSize {
         guard let image = image else { return NSSize(width: 0, height: 0) }
-        let thumbnailHeightMax = ThumbnailView.maxThumbnailHeight(screen)
+        let thumbnailHeightMax = ThumbnailView.maxThumbnailHeight()
             - Appearance.edgeInsetsSize * 2
             - Appearance.intraCellPadding
             - Appearance.iconSize
-        let thumbnailWidthMax = ThumbnailView.maxThumbnailWidth(screen)
+        let thumbnailWidthMax = ThumbnailView.maxThumbnailWidth()
             - Appearance.edgeInsetsSize * 2
         // don't stretch very small windows; keep them 1:1 in the switcher
         if !isWindowlessApp && image.size.width < thumbnailWidthMax && image.size.height < thumbnailHeightMax {
@@ -559,9 +575,9 @@ class ThumbnailView: FlippedView {
         return NSSize(width: width.rounded(), height: height.rounded())
     }
 
-    static func iconSize(_ screen: NSScreen) -> NSSize {
+    static func iconSize() -> NSSize {
         if Preferences.appearanceStyle == .appIcons {
-            let widthMin = ThumbnailView.minThumbnailWidth(screen)
+            let widthMin = ThumbnailView.minThumbnailWidth()
             let contentWidth = Appearance.iconSize
             let frameWidth = contentWidth + Appearance.edgeInsetsSize * 2
             let width = max(frameWidth, widthMin).rounded()
@@ -573,12 +589,12 @@ class ThumbnailView: FlippedView {
         return NSSize(width: Appearance.iconSize, height: Appearance.iconSize)
     }
 
-    static func height(_ screen: NSScreen, _ labelHeight: CGFloat) -> CGFloat {
+    static func height(_ labelHeight: CGFloat) -> CGFloat {
         if Preferences.appearanceStyle == .titles {
-            return max(ThumbnailView.iconSize(screen).height, labelHeight) + Appearance.edgeInsetsSize * 2
+            return max(ThumbnailView.iconSize().height, labelHeight) + Appearance.edgeInsetsSize * 2
         } else if Preferences.appearanceStyle == .appIcons {
-            return ThumbnailView.iconSize(screen).height + Appearance.edgeInsetsSize * 2 + Appearance.intraCellPadding * 2 + labelHeight
+            return ThumbnailView.iconSize().height + Appearance.edgeInsetsSize * 2 + Appearance.intraCellPadding * 2 + labelHeight
         }
-        return ThumbnailView.maxThumbnailHeight(screen).rounded(.down)
+        return ThumbnailView.maxThumbnailHeight()
     }
 }
diff --git a/src/ui/main-window/ThumbnailsPanel.swift b/src/ui/main-window/ThumbnailsPanel.swift
index 18755e22..67d00158 100644
--- a/src/ui/main-window/ThumbnailsPanel.swift
+++ b/src/ui/main-window/ThumbnailsPanel.swift
@@ -44,12 +44,12 @@ class ThumbnailsPanel: NSPanel {
         thumbnailsView.scrollView.flashScrollers()
     }
 
-    static func maxThumbnailsWidth(_ screen: NSScreen) -> CGFloat {
-        return screen.frame.width * Appearance.maxWidthOnScreen - Appearance.windowPadding * 2
+    static func maxThumbnailsWidth() -> CGFloat {
+        return (NSScreen.preferred.frame.width * Appearance.maxWidthOnScreen - Appearance.windowPadding * 2).rounded()
     }
 
-    static func maxThumbnailsHeight(_ screen: NSScreen) -> CGFloat {
-        return screen.frame.height * Appearance.maxHeightOnScreen - Appearance.windowPadding * 2
+    static func maxThumbnailsHeight() -> CGFloat {
+        return (NSScreen.preferred.frame.height * Appearance.maxHeightOnScreen - Appearance.windowPadding * 2).rounded()
     }
 }
 
diff --git a/src/ui/main-window/ThumbnailsView.swift b/src/ui/main-window/ThumbnailsView.swift
index 39d447dd..8f92d8b7 100644
--- a/src/ui/main-window/ThumbnailsView.swift
+++ b/src/ui/main-window/ThumbnailsView.swift
@@ -22,6 +22,7 @@ class ThumbnailsView: NSVisualEffectView {
     func reset() {
         // it would be nicer to remove this whole "reset" logic, and instead update each component to check Appearance properties before showing
         // Maybe in some Appkit willDraw() function that triggers before drawing it
+        NSScreen.updatePreferred()
         Appearance.update()
         material = Appearance.material
         for i in 0..<ThumbnailsView.recycledViews.count {
@@ -101,10 +102,10 @@ class ThumbnailsView: NSVisualEffectView {
         }
     }
 
-    func updateItemsAndLayout(_ screen: NSScreen) {
-        let widthMax = ThumbnailsPanel.maxThumbnailsWidth(screen).rounded()
-        if let (maxX, maxY, labelHeight) = layoutThumbnailViews(screen, widthMax) {
-            layoutParentViews(screen, maxX, widthMax, maxY, labelHeight)
+    func updateItemsAndLayout() {
+        let widthMax = ThumbnailsPanel.maxThumbnailsWidth().rounded()
+        if let (maxX, maxY, labelHeight) = layoutThumbnailViews(widthMax) {
+            layoutParentViews(maxX, widthMax, maxY, labelHeight)
             if Preferences.alignThumbnails == .center {
                 centerRows(maxX)
             }
@@ -120,9 +121,9 @@ class ThumbnailsView: NSVisualEffectView {
         }
     }
 
-    private func layoutThumbnailViews(_ screen: NSScreen, _ widthMax: CGFloat) -> (CGFloat, CGFloat, CGFloat)? {
+    private func layoutThumbnailViews(_ widthMax: CGFloat) -> (CGFloat, CGFloat, CGFloat)? {
         let labelHeight = ThumbnailsView.recycledViews.first!.label.cell!.cellSize.height
-        let height = ThumbnailView.height(screen, labelHeight)
+        let height = ThumbnailView.height(labelHeight)
         let isLeftToRight = App.shared.userInterfaceLayoutDirection == .leftToRight
         let startingX = isLeftToRight ? Appearance.interCellPadding : widthMax - Appearance.interCellPadding
         var currentX = startingX
@@ -136,7 +137,7 @@ class ThumbnailsView: NSVisualEffectView {
             guard App.app.appIsBeingUsed else { return nil }
             guard window.shouldShowTheUser else { continue }
             let view = ThumbnailsView.recycledViews[index]
-            view.updateRecycledCellWithNewContent(window, index, height, screen)
+            view.updateRecycledCellWithNewContent(window, index, height)
             let width = view.frame.size.width
             let projectedX = projectedWidth(currentX, width).rounded(.down)
             if needNewLine(projectedX, widthMax) {
@@ -177,8 +178,8 @@ class ThumbnailsView: NSVisualEffectView {
         App.shared.userInterfaceLayoutDirection == .leftToRight ? currentX : currentX - width
     }
 
-    private func layoutParentViews(_ screen: NSScreen, _ maxX: CGFloat, _ widthMax: CGFloat, _ maxY: CGFloat, _ labelHeight: CGFloat) {
-        let heightMax = ThumbnailsPanel.maxThumbnailsHeight(screen).rounded()
+    private func layoutParentViews(_ maxX: CGFloat, _ widthMax: CGFloat, _ maxY: CGFloat, _ labelHeight: CGFloat) {
+        let heightMax = ThumbnailsPanel.maxThumbnailsHeight()
         ThumbnailsView.thumbnailsWidth = min(maxX, widthMax)
         ThumbnailsView.thumbnailsHeight = min(maxY, heightMax)
         let frameWidth = ThumbnailsView.thumbnailsWidth + Appearance.windowPadding * 2