refactor(compositor): reduce unnecessary UI updates

- Defer updates when window state hasn't actually changed
- Cache frame-blocked state per screen instead of recalculating constantly
- keep popouts cache so reopening them is instant & clean up otherwise

quickshell/Services/CompositorService.qml

@@ -135,11 +135,34 @@ Singleton {
         repeat: false
         onTriggered: {
             _sortScheduled = false;
-            sortedToplevels = computeSortedToplevels();
+            const next = computeSortedToplevels();
+            // Avoid reassigning (and invalidating bindings) when contents are equivalent.
+            if (!_toplevelListEquivalent(next, sortedToplevels))
+                sortedToplevels = next;
+            _recomputeFrameBlocked();
             toplevelsChanged();
         }
     }
 
+    function _toplevelListEquivalent(a, b) {
+        if (!a || !b || a.length !== b.length)
+            return false;
+        for (let i = 0; i < a.length; i++) {
+            const x = a[i];
+            const y = b[i];
+            if (x === y)
+                continue;
+            if (!x || !y)
+                return false;
+            // Only niri's enriched snapshots support value comparison.
+            if (x.niriWindowId === undefined || y.niriWindowId === undefined)
+                return false;
+            if (x.niriWindowId !== y.niriWindowId || x.niriWorkspaceId !== y.niriWorkspaceId || x.appId !== y.appId || x.title !== y.title || !!x.activated !== !!y.activated || !!x.fullscreen !== !!y.fullscreen || !!x.maximized !== !!y.maximized || !!x.minimized !== !!y.minimized)
+                return false;
+        }
+        return true;
+    }
+
     function scheduleSort() {
         if (_sortScheduled)
             return;
@@ -164,8 +187,10 @@ Singleton {
                     if (event.name === "workspace" || event.name === "workspacev2" || event.name === "focusedmon" || event.name === "focusedmonv2" || event.name === "activespecial")
                         Hyprland.refreshMonitors();
                 } catch (e) {}
-                if (event.name === "activespecial")
+                if (event.name === "activespecial") {
                     root.updateHyprlandVisibleSpecialWorkspaces(event);
+                    root._recomputeFrameBlocked();
+                }
                 root.scheduleSort();
             }
         }
@@ -175,6 +200,10 @@ Singleton {
         function onWindowsChanged() {
             root.scheduleSort();
         }
+        // Workspace switches affect the fullscreen check's active workspace.
+        function onAllWorkspacesChanged() {
+            root._recomputeFrameBlocked();
+        }
     }
 
     Component.onCompleted: {
@@ -182,6 +211,7 @@ Singleton {
         detectCompositor();
         updateHyprlandVisibleSpecialWorkspaces(null);
         scheduleSort();
+        _recomputeFrameBlocked();
         Qt.callLater(() => {
             NiriService.generateNiriLayoutConfig();
             HyprlandService.generateLayoutConfig();
@@ -592,10 +622,74 @@ Singleton {
         return false;
     }
 
-    function connectedFrameBlockedOnScreen(screenOrName) {
-        if (hasFullscreenToplevelOnScreen(screenOrName))
+    // Per-screen cache for connectedFrameBlockedOnScreen to avoid recomputing on every consumer binding.
+    property var frameBlockedByScreen: ({})
+
+    function _computeConnectedFrameBlocked(screenName) {
+        if (hasFullscreenToplevelOnScreen(screenName))
             return true;
-        return hyprlandSpecialWorkspaceBlocksConnectedFrame(screenOrName);
+        return hyprlandSpecialWorkspaceBlocksConnectedFrame(screenName);
+    }
+
+    function _recomputeFrameBlocked() {
+        const screens = Quickshell.screens || [];
+        const next = {};
+        let changed = false;
+        for (let i = 0; i < screens.length; i++) {
+            const name = screens[i]?.name;
+            if (!name)
+                continue;
+            const blocked = _computeConnectedFrameBlocked(name);
+            next[name] = blocked;
+            if (frameBlockedByScreen[name] !== blocked)
+                changed = true;
+        }
+        if (!changed) {
+            for (const name in frameBlockedByScreen) {
+                if (!(name in next)) {
+                    changed = true;
+                    break;
+                }
+            }
+        }
+        if (changed)
+            frameBlockedByScreen = next;
+    }
+
+    function connectedFrameBlockedOnScreen(screenOrName) {
+        const screenName = _screenName(screenOrName);
+        if (!screenName)
+            return false;
+        const cached = frameBlockedByScreen[screenName];
+        if (cached !== undefined)
+            return cached;
+        return _computeConnectedFrameBlocked(screenName);
+    }
+
+    Connections {
+        target: ToplevelManager
+        function onActiveToplevelChanged() {
+            root._recomputeFrameBlocked();
+        }
+    }
+
+    // Track active toplevel's fullscreen/activated state directly (no per-property signals from ToplevelManager).
+    Connections {
+        target: ToplevelManager.activeToplevel
+        ignoreUnknownSignals: true
+        function onFullscreenChanged() {
+            root._recomputeFrameBlocked();
+        }
+        function onActivatedChanged() {
+            root._recomputeFrameBlocked();
+        }
+    }
+
+    Connections {
+        target: Quickshell
+        function onScreensChanged() {
+            root._recomputeFrameBlocked();
+        }
     }
 
     function _screenForName(screenOrName) {

quickshell/Services/NiriService.qml

@@ -435,26 +435,31 @@ Singleton {
     function handleWindowFocusChanged(data) {
         const focusedWindowId = data.id;
 
+        // Only clone windows whose focus flag changes; skip reassignment if nothing changed.
         let focusedWindow = null;
-        const updatedWindows = [];
+        let changed = false;
+        const updatedWindows = new Array(windows.length);
 
         for (var i = 0; i < windows.length; i++) {
             const w = windows[i];
-            const updatedWindow = {};
-
-            for (let prop in w) {
-                updatedWindow[prop] = w[prop];
+            const isFocused = w.id === focusedWindowId;
+            if (!!w.is_focused === isFocused) {
+                updatedWindows[i] = w;
+                if (isFocused)
+                    focusedWindow = w;
+                continue;
             }
-
-            updatedWindow.is_focused = (w.id === focusedWindowId);
-            if (updatedWindow.is_focused) {
+            const updatedWindow = Object.assign({}, w, {
+                "is_focused": isFocused
+            });
+            if (isFocused)
                 focusedWindow = updatedWindow;
-            }
-
-            updatedWindows.push(updatedWindow);
+            updatedWindows[i] = updatedWindow;
+            changed = true;
         }
 
-        windows = updatedWindows;
+        if (changed)
+            windows = updatedWindows;
 
         if (focusedWindow) {
             const ws = root.workspaces[focusedWindow.workspace_id];
@@ -490,26 +495,29 @@ Singleton {
             setWorkspaces(updatedWorkspaces);
         }
 
-        const updatedWindows = [];
+        let changed = false;
+        const updatedWindows = new Array(windows.length);
 
         for (var i = 0; i < windows.length; i++) {
             const w = windows[i];
-            const updatedWindow = {};
-
-            for (let prop in w) {
-                updatedWindow[prop] = w[prop];
-            }
-
+            let isFocused;
             if (data.active_window_id !== null && data.active_window_id !== undefined) {
-                updatedWindow.is_focused = (w.id == data.active_window_id);
+                isFocused = (w.id == data.active_window_id);
             } else {
-                updatedWindow.is_focused = w.workspace_id == data.workspace_id ? false : w.is_focused;
+                isFocused = w.workspace_id == data.workspace_id ? false : !!w.is_focused;
             }
-
-            updatedWindows.push(updatedWindow);
+            if (!!w.is_focused === isFocused) {
+                updatedWindows[i] = w;
+                continue;
+            }
+            updatedWindows[i] = Object.assign({}, w, {
+                "is_focused": isFocused
+            });
+            changed = true;
         }
 
-        windows = updatedWindows;
+        if (changed)
+            windows = updatedWindows;
     }
 
     function handleWindowsChanged(data) {

quickshell/Services/PopoutService.qml

@@ -58,6 +58,65 @@ Singleton {
     property string pendingThemeInstall: ""
     property string pendingPluginInstall: ""
 
+    // Deferred unload: keep popouts warm while the session is active and reclaim them on lock/monitors-off.
+    property var _pendingUnloads: ({})
+
+    Connections {
+        target: SessionService
+        function onSessionLocked() {
+            root._flushPendingUnloads();
+        }
+    }
+
+    Connections {
+        target: IdleService
+        function onMonitorsOffChanged() {
+            if (IdleService.monitorsOff)
+                root._flushPendingUnloads();
+        }
+    }
+
+    function _scheduleUnload(key) {
+        _pendingUnloads[key] = true;
+    }
+
+    function _flushPendingUnloads() {
+        const keys = Object.keys(_pendingUnloads);
+        _pendingUnloads = ({});
+        for (let i = 0; i < keys.length; i++) {
+            const unload = _deferredUnloaders[keys[i]];
+            if (unload)
+                unload();
+        }
+    }
+
+    function _popoutStillPresented(popout) {
+        return !!popout && (popout.shouldBeVisible === true || popout.isClosing === true);
+    }
+
+    function _unloadPopoutNow(popoutName, loaderName) {
+        const loader = root[loaderName];
+        if (!loader)
+            return;
+        if (_popoutStillPresented(root[popoutName]))
+            return;
+        root[popoutName] = null;
+        loader.active = false;
+    }
+
+    readonly property var _deferredUnloaders: ({
+            "controlCenter": () => _unloadPopoutNow("controlCenterPopout", "controlCenterLoader"),
+            "notificationCenter": () => _unloadPopoutNow("notificationCenterPopout", "notificationCenterLoader"),
+            "appDrawer": () => _unloadPopoutNow("appDrawerPopout", "appDrawerLoader"),
+            "processList": () => _unloadPopoutNow("processListPopout", "processListPopoutLoader"),
+            "battery": () => _unloadPopoutNow("batteryPopout", "batteryPopoutLoader"),
+            "vpn": () => _unloadPopoutNow("vpnPopout", "vpnPopoutLoader"),
+            "systemUpdate": () => _unloadPopoutNow("systemUpdatePopout", "systemUpdateLoader"),
+            "layout": () => _unloadPopoutNow("layoutPopout", "layoutPopoutLoader"),
+            "clipboardHistory": () => _unloadPopoutNow("clipboardHistoryPopout", "clipboardHistoryPopoutLoader"),
+            "settings": () => _unloadSettingsNow()
+        })
+
     function setPosition(popout, x, y, width, section, screen) {
         if (popout && popout.setTriggerPosition && arguments.length >= 6) {
             popout.setTriggerPosition(x, y, width, section, screen);
@@ -76,10 +135,7 @@ Singleton {
     }
 
     function unloadControlCenter() {
-        if (!controlCenterLoader)
-            return;
-        controlCenterPopout = null;
-        controlCenterLoader.active = false;
+        _scheduleUnload("controlCenter");
     }
 
     function toggleControlCenter(x, y, width, section, screen) {
@@ -101,10 +157,7 @@ Singleton {
     }
 
     function unloadNotificationCenter() {
-        if (!notificationCenterLoader)
-            return;
-        notificationCenterPopout = null;
-        notificationCenterLoader.active = false;
+        _scheduleUnload("notificationCenter");
     }
 
     function toggleNotificationCenter(x, y, width, section, screen) {
@@ -126,10 +179,7 @@ Singleton {
     }
 
     function unloadAppDrawer() {
-        if (!appDrawerLoader)
-            return;
-        appDrawerPopout = null;
-        appDrawerLoader.active = false;
+        _scheduleUnload("appDrawer");
     }
 
     function toggleAppDrawer(x, y, width, section, screen) {
@@ -151,10 +201,7 @@ Singleton {
     }
 
     function unloadProcessListPopout() {
-        if (!processListPopoutLoader)
-            return;
-        processListPopout = null;
-        processListPopoutLoader.active = false;
+        _scheduleUnload("processList");
     }
 
     function toggleProcessList(x, y, width, section, screen) {
@@ -268,10 +315,7 @@ Singleton {
     }
 
     function unloadBattery() {
-        if (!batteryPopoutLoader)
-            return;
-        batteryPopout = null;
-        batteryPopoutLoader.active = false;
+        _scheduleUnload("battery");
     }
 
     function toggleBattery(x, y, width, section, screen) {
@@ -293,10 +337,7 @@ Singleton {
     }
 
     function unloadVpn() {
-        if (!vpnPopoutLoader)
-            return;
-        vpnPopout = null;
-        vpnPopoutLoader.active = false;
+        _scheduleUnload("vpn");
     }
 
     function toggleVpn(x, y, width, section, screen) {
@@ -319,10 +360,7 @@ Singleton {
     }
 
     function unloadSystemUpdate() {
-        if (!systemUpdateLoader)
-            return;
-        systemUpdatePopout = null;
-        systemUpdateLoader.active = false;
+        _scheduleUnload("systemUpdate");
     }
 
     function toggleSystemUpdate(x, y, width, section, screen) {
@@ -441,10 +479,16 @@ Singleton {
     }
 
     function unloadSettings() {
-        if (settingsModalLoader) {
-            settingsModal = null;
-            settingsModalLoader.active = false;
-        }
+        _scheduleUnload("settings");
+    }
+
+    function _unloadSettingsNow() {
+        if (!settingsModalLoader)
+            return;
+        if (settingsModal && settingsModal.visible)
+            return;
+        settingsModal = null;
+        settingsModalLoader.active = false;
     }
 
     function _onSettingsModalLoaded() {
@@ -484,17 +528,11 @@ Singleton {
     }
 
     function unloadClipboardHistoryPopout() {
-        if (!clipboardHistoryPopoutLoader)
-            return;
-        clipboardHistoryPopout = null;
-        clipboardHistoryPopoutLoader.active = false;
+        _scheduleUnload("clipboardHistory");
     }
 
     function unloadLayoutPopout() {
-        if (!layoutPopoutLoader)
-            return;
-        layoutPopout = null;
-        layoutPopoutLoader.active = false;
+        _scheduleUnload("layout");
     }
 
     property bool _dankLauncherV2WantsOpen: false

quickshell/Widgets/DankPopout.qml

@@ -134,12 +134,7 @@ Item {
         }
     }
 
-    Connections {
-        target: CompositorService
-        function onToplevelsChanged() {
-            root._maybeResolveBackend();
-        }
-    }
+    // Backend re-resolution on toplevel activity is covered by CompositorService.frameBlockedByScreen.
 
     function _usesConnectedBackendForScreen(targetScreen) {
         return CompositorService.usesConnectedFrameChromeForScreen(targetScreen);

quickshell/Widgets/DankPopoutConnected.qml

@@ -38,6 +38,7 @@ Item {
     property bool contentHandlesKeys: false
     property bool fullHeightSurface: false
     property bool _primeContent: false
+    property bool _contentWarm: false
     property bool _resizeActive: false
     property real _chromeAnimTravelX: 1
     property real _chromeAnimTravelY: 1
@@ -472,6 +473,7 @@ Item {
         isClosing = false;
         animationsEnabled = false;
         _primeContent = true;
+        _contentWarm = true;
         _supersededClose = false;
 
         const screenChanged = _lastOpenedScreen !== null && _lastOpenedScreen !== screen;
@@ -1334,7 +1336,8 @@ Item {
                         Loader {
                             id: contentLoader
                             anchors.fill: parent
-                            active: root._primeContent || shouldBeVisible || contentWindow.visible
+                            // _contentWarm keeps the tree loaded across close for fast re-open; reclaimed by PopoutService on lock/idle.
+                            active: root._primeContent || shouldBeVisible || contentWindow.visible || root._contentWarm
                             asynchronous: false
                         }
                     }

quickshell/Widgets/DankPopoutStandalone.qml

@@ -57,6 +57,7 @@ Item {
     property bool contentHandlesKeys: false
     property bool fullHeightSurface: false
     property bool _primeContent: false
+    property bool _contentWarm: false
     property bool _resizeActive: false
     property real _surfaceMarginLeft: 0
     property real _surfaceMarginTop: 0
@@ -305,6 +306,7 @@ Item {
         isClosing = false;
         animationsEnabled = false;
         _primeContent = true;
+        _contentWarm = true;
 
         _frozenMaskX = maskX;
         _frozenMaskY = maskY;
@@ -891,7 +893,8 @@ Item {
                         Loader {
                             id: contentLoader
                             anchors.fill: parent
-                            active: root._primeContent || shouldBeVisible || contentWindow.visible
+                            // _contentWarm keeps the tree loaded across close for fast re-open; reclaimed by PopoutService on lock/idle.
+                            active: root._primeContent || shouldBeVisible || contentWindow.visible || root._contentWarm
                             asynchronous: false
                         }
                     }