Should dynamic import()ed script loading delay Window load events? #5824
Description
Example:
<body onload="console.log('Window load event')">
<script>
// Executed after 1 sec.
setTimeout(() => console.log('loading'), 1000);
// Resolved after 2 sec loading
import('./slow-script-taking-2sec-to-load.js').then(() => console.log('imported'));
</script>
</body>
WPT: web-platform-tests/wpt#25005
- Spec:
Window load event/loading/imported.- Dynamic imports don't seem to
#delay-the-load-event. Therefore, Window load event would be fired even while dynamic imports are loading.
- Dynamic imports don't seem to
- Chromium:
loading/Window load event/imported.- The Window load event is delayed until finishing loading dynamically imported scripts, but not until the
thencallback ofimport()promise. Just after the load finish, a Window load event is fired and then thethencallback ofimport()promise.
- The Window load event is delayed until finishing loading dynamically imported scripts, but not until the
- Firefox and Safari:
loading/imported/Window load event.- The Window load event seems delayed until the
thencallback ofimport()promise.
- The Window load event seems delayed until the
Given that all browsers delay the load event, perhaps it's better to make the spec also delay the load event, e.g. by changing https://html.spec.whatwg.org/multipage/webappapis.html#hostimportmoduledynamically(referencingscriptormodule,-specifier,-promisecapability).