Fix issue with line break node breaking schema export

Author: harbournick

examples/shared/vue/UploadFile/UploadFile.vue

@@ -0,0 +1,30 @@
+<script setup>
+import { ref } from 'vue';
+const fileInput = ref(null);
+
+const props = defineProps({
+  updateFile: {
+    type: Function,
+    required: true
+  }
+})
+
+const handleFileChange = () => {
+  console.debug('File input changed');
+  props.updateFile(fileInput.value.files[0]);
+}
+
+</script>
+
+<template>
+  <div>
+    <button class="custom-button" @click="fileInput?.click()">Import document</button>
+    <input 
+        type="file" 
+        ref="fileInput" 
+        accept=".docx" 
+        class="hidden"
+        @change="handleFileChange"
+      >
+  </div>
+</template>

packages/super-editor/src/extensions/line-break/line-break.js

@@ -2,17 +2,20 @@ import { Node, Attribute } from '@core/index.js';
 
 export const LineBreak = Node.create({
   name: 'lineBreak',
-
   group: 'inline',
-
   inline: true,
+  marks: '',
+  defining: true,
+  selectable: false,
+  content: '',
+  atom: true,
 
   parseDOM() {
     return [{ tag: 'br' }];
   },
 
   renderDOM() {
-    return ['br', {}, 0];
+    return ['br', {}];
   },
 });