How can I tell if a config entity hasn’t been saved yet? How can I tell if a config entity hasn’t been saved yet?
isNew();


this core test confirms it:


// Config is no longer new once saved.
$this-&gt;config-&gt;save();
$this-&gt;assertFalse($this-&gt;config-&gt;isNew());



(from core/tests/Drupal/Tests/Core/Config/ConfigTest.php)