diff --git a/packages/block-library/src/classic/edit.js b/packages/block-library/src/classic/edit.js
index 8195e51006af4..1fbc892ea7cd9 100644
--- a/packages/block-library/src/classic/edit.js
+++ b/packages/block-library/src/classic/edit.js
@@ -54,7 +54,11 @@ export default class ClassicEdit extends Component {
 		if ( document.readyState === 'complete' ) {
 			this.initialize();
 		} else {
-			window.addEventListener( 'DOMContentLoaded', this.initialize );
+			document.addEventListener( 'readystatechange', () => {
+				if ( document.readyState === 'complete' ) {
+					this.initialize();
+				}
+			} );
 		}
 	}