diff --git a/packages/lexical/src/LexicalEditor.ts b/packages/lexical/src/LexicalEditor.ts
index 4798f4d8118..76de3af0278 100644
--- a/packages/lexical/src/LexicalEditor.ts
+++ b/packages/lexical/src/LexicalEditor.ts
@@ -71,7 +71,7 @@ export type TextNodeThemeClasses = {
   italic?: EditorThemeClassName;
   lowercase?: EditorThemeClassName;
   uppercase?: EditorThemeClassName;
-  capitalize: EditorThemeClassName;
+  capitalize?: EditorThemeClassName;
   strikethrough?: EditorThemeClassName;
   subscript?: EditorThemeClassName;
   superscript?: EditorThemeClassName;