check if the canvas is separated

test/e2e/specs/site-editor/zoom-out.spec.js

@@ -35,5 +35,22 @@ test.describe( 'Zoom Out', () => {
 
 		//Check that the iframe is larger than the html
 		expect( iframeRect.width ).toBeGreaterThan( htmlRect.width );
+
+		//Check that the zoomed out content has a frame around it
+		expect( htmlRect.x ).toBeGreaterThan( iframeRect.x );
+
+		//We use border to separate the content from the frame so we need
+		//to check that that is present too, since boundingBox()
+		//includes the border to calculate the position
+		const borderWidths = await html.evaluate( ( el ) => {
+			const styles = window.getComputedStyle( el );
+			return {
+				top: parseFloat( styles.borderTopWidth ),
+				right: parseFloat( styles.borderRightWidth ),
+				bottom: parseFloat( styles.borderBottomWidth ),
+				left: parseFloat( styles.borderLeftWidth ),
+			};
+		} );
+		expect( htmlRect.y + borderWidths.top ).toBeGreaterThan( iframeRect.y );
 	} );
 } );