Fix: initialize undomanager for empty document

Signed-off-by: Benjamin Frueh <[email protected]>

Author: benjaminfrueh

src/components/Editor.vue

@@ -485,6 +485,25 @@ export default defineComponent({
 			this.idle = false
 		},
 
+    initUndoManagerForEmptyDocument() {
+      if (this.editor.state.doc.textContent.length > 0 || !this.editor.isEditable) {
+        return
+      }
+
+      if (!this.editor.commands.insertContent(' ')) {
+        return
+      }
+
+      this.editor.commands.deleteRange({ from: 0, to: 1 })
+
+      const undoManager = this.editor.state.plugins
+          .map(p => p.getState?.(this.editor.state)?.undoManager)
+          .find(um => um?.clear)
+      undoManager?.clear()
+
+      this.dirty = false
+    },
+
 		onOpened({ document, session, content, documentState, readOnly }) {
 			this.document = document
 			this.readOnly = readOnly
@@ -520,6 +539,7 @@ export default defineComponent({
 						isRichEditor: this.isRichEditor,
 					})
 				}
+        this.initUndoManagerForEmptyDocument()
 			})
 			this.updateUser(session)
 		},