Decrement a given field value
This method does not modify the existing
$page object but returns a new object with the changes applied. Learn more →
Kirby\Cms\Page inherited from
Kirby's objects are immutable. That means, when you modify an object like
$file etc. using a method like
changeTitle() and so on, a new object is returned. Therefore, you have to store the returned object in a new variable to be able to further work with it.