page.changeSlug:before

/site/config/config.php

return [
    'hooks' => [
        'page.changeSlug:before' => function (Kirby\Cms\Page $page, string $slug, ?string $languageCode = null) {
            // your code goes here
        }
    ]
]

Parameters

Parameter	Type
$page	Kirby\Cms\Page
$slug	string
$languageCode	string|null