blur: clip regions to the window so hyprland stops blurring whole surfaces

fixes #3480

quickshell/Widgets/DankSlideout.qml

@@ -120,7 +120,12 @@ PanelWindow {
     readonly property real alignedEdgeGap: Theme.px(edgeGap, dpr)
     readonly property real slideoutSlideSnapX: Theme.snap(slideContainer.slideOffset, dpr)
 
-    onIsVisibleChanged: slideSpring.retarget(isVisible ? 0 : (slideFromLeft ? -slideContainer.width : slideContainer.width))
+    onIsVisibleChanged: {
+        slideSpring.retarget(isVisible ? 0 : (slideFromLeft ? -slideContainer.width : slideContainer.width));
+        if (isVisible || slideSpring.running)
+            return;
+        mappedVisible = false;
+    }
 
     mask: Region {
         item: Rectangle {

quickshell/Widgets/WindowBlur.qml

@@ -50,6 +50,13 @@ Item {
             width: root.clipEnabled ? root.clipWidth : root.blurWidth
             height: root.clipEnabled ? root.clipHeight : root.blurHeight
         }
+
+        // Hyprland blurs the whole surface when the region lies entirely outside it
+        Region {
+            intersection: Intersection.Intersect
+            width: root.targetWindow?.width ?? 0
+            height: root.targetWindow?.height ?? 0
+        }
     }
 
     function _apply() {