sized screenSpaceCanvas use CanvasCacheStratery should use self size.

canvas2D/src/Engine/babylon.canvas2d.ts

@@ -1047,6 +1047,10 @@
             this._setupInteraction(enable);
         }
 
+        public get fitRenderingDevice(): boolean {
+            return this._fitRenderingDevice;
+        }
+
         public get designSize(): Size {
             return this._designSize;
         }

canvas2D/src/Engine/babylon.group2d.ts

@@ -830,8 +830,13 @@
             }
 
             if (isCanvas && this.owner.cachingStrategy===Canvas2D.CACHESTRATEGY_CANVAS && this.owner.isScreenSpace) {
-                Group2D._s.width = this.owner.engine.getRenderWidth();
-                Group2D._s.height = this.owner.engine.getRenderHeight();
+                if(this.owner.designSize || this.owner.fitRenderingDevice){
+                    Group2D._s.width = this.owner.engine.getRenderWidth();
+                    Group2D._s.height = this.owner.engine.getRenderHeight();
+                }
+                else{
+                    Group2D._s.copyFrom(this.owner.size);
+                }
             } else {
                 Group2D._s.width = Math.ceil(this.actualSize.width * scale.x * rs);
                 Group2D._s.height = Math.ceil(this.actualSize.height * scale.y * rs);