Here is an informative write-up regarding the requirement to install version 0.9.9 or later.
// Show an update prompt EditorUtility.DisplayDialog("Update PlayerAnimator", "Please install PlayerAnimator version " + REQUIRED_VERSION + " or later.", "Update"); // Open the update URL Application.OpenURL("https://github.com/PlayerAnimator/PlayerAnimator/releases"); install playeranimator version 099 or later better
Example: