ENGCOM-8494: Add event listeners passive for fotorama lib improves lighthouse metrics #31080

magento-engcom-team · magento-engcom-team · commit 2f5b57a0c0e2 · 2021-04-09T05:05:28.000-05:00
- Merge Pull Request #31080 from mrtuvn/magento2:add-event-listener-passive-for-fotorama - Merged commits: 1. 67c2c71
diff --git a/lib/web/fotorama/fotorama.js b/lib/web/fotorama/fotorama.js
@@ -1140,7 +1140,7 @@ fotoramaVersion = '4.6.4';
 
     function addEvent(el, e, fn, bool) {
         if (!e) return;
-        el.addEventListener ? el.addEventListener(e, fn, !!bool) : el.attachEvent('on' + e, fn);
+        el.addEventListener ? el.addEventListener(e, fn, {passive: true}) : el.attachEvent('on' + e, fn);
     }
 
     /**

Original file line number	Diff line number	Diff line change
`@@ -1140,7 +1140,7 @@ fotoramaVersion = '4.6.4';`
`1140`	`1140`
`1141`	`1141`	`function addEvent(el, e, fn, bool) {`
`1142`	`1142`	`if (!e) return;`
`1143`		`- el.addEventListener ? el.addEventListener(e, fn, !!bool) : el.attachEvent('on' + e, fn);`
	`1143`	`+ el.addEventListener ? el.addEventListener(e, fn, {passive: true}) : el.attachEvent('on' + e, fn);`
`1144`	`1144`	`}`
`1145`	`1145`
`1146`	`1146`	`/**`