Add aria-hidden to resize listener object. Fixes #3948.

src/runtime/internal/dom.ts

@@ -237,6 +237,7 @@ export function add_resize_listener(element, fn) {
 
 	const object = document.createElement('object');
 	object.setAttribute('style', 'display: block; position: absolute; top: 0; left: 0; height: 100%; width: 100%; overflow: hidden; pointer-events: none; z-index: -1;');
+	object.setAttribute('aria-hidden', 'true');
 	object.type = 'text/html';
 	object.tabIndex = -1;
 

test/runtime/samples/binding-width-height-a11y/_config.js

@@ -0,0 +1,8 @@
+export default {
+	async test({ assert, target }) {
+		const object = target.querySelector('object');
+
+		assert.equal(object.getAttribute('aria-hidden'), "true");
+		assert.equal(object.getAttribute('tabindex'), "-1");
+	}
+};

test/runtime/samples/binding-width-height-a11y/main.svelte

@@ -0,0 +1,10 @@
+<script>
+	let offsetWidth = 0;
+	let offsetHeight = 0;
+</script>
+
+<div bind:offsetHeight bind:offsetWidth>
+
+	<h1>Hello</h1>
+
+</div>