Fix issue 943 (#965)

docs/CHANGELOG.md

@@ -7,6 +7,7 @@
 — `New` *API* — Block [lifecycle hooks](tools.md#block-lifecycle-hooks)
 - `Fix` — On selection from end to start backspace is working as expected now [#869](https://github.com/codex-team/editor.js/issues/869)
 — `Fix` — Fix flipper with empty dom iterator [#926](https://github.com/codex-team/editor.js/issues/926)
+- `Fix` — Normalize node before walking through children at `isEmpty` method [943](https://github.com/codex-team/editor.js/issues/943)
 
 ### 2.15.1
 

src/components/dom.ts

@@ -370,6 +370,11 @@ export default class Dom {
       return this.isNodeEmpty(node);
     }
 
+    /**
+     * Normalize node to merge several text nodes to one to reduce tree walker iterations
+     */
+    node.normalize();
+
     treeWalker.push(node.firstChild);
 
     while ( treeWalker.length > 0 ) {