How to show floppy disk UTF-16 character on custom inspector button?

There is a nice floppy disk icon in Unicode that I'd like to put on a "save" button. I've been successful showing other Unicode-based icons on the button, but using the floppy disk code, results in blank button with no image/text on it. Maybe there is no support for UTF-16 icons, and they need to be UTF-8 only? Current code below:

     [CustomEditor(typeof(Gestures))]
     public class GesturesEditor : Editor {
         private static GUIContent saveButtonContent = new GUIContent("\U0001f4be", "Save");
     
         public override void OnInspectorGUI() {
             serializedObject.Update();
             GUILayout.Button(saveButtonContent);
             serializedObject.ApplyModifiedProperties();
         }
    }