[v4] Kirby\Cms\Core::{closure}(): Return value must be of type string, null returned

If tapping the search icon on the panel, this error is presented. I cannot seem to find a way to debug it.

Please give us more information, as it is difficult to research the cause with the few details available. The cause may be in the template, in the controller or elsewhere.

Have you used this cookbook and checked all the steps again?

There seems to be an error with the SEO plugin (GitHub - fabianmichael/kirby-meta: All-in-one solution to all of your SEO/OpenGraph/JSON-LD needs. 👀)

    'hooks' => [
        'meta.load:after' => function (
            array $metadata,
            Kirby\Cms\Page $page,
            ?string $languageCode
        ) {
            if (empty($metadata['og_image']) === true) {
                $metadata['og_image'] = $page->images()->findBy('template', 'image') ?? $page->images()->first();
            }
            if (empty($metadata['meta_description']) === true) {
                $metadata['meta_description'] = $page->rezumat()->excerpt(155)->or($page->text()->excerpt(155));
            }
            return $metadata;
        },
    ],

This hook seems to hijack the search feature or interfere with the normal behaviour

Ok, apparently the plugin added a search icon identical to the search one at the top for whatever reason.

Perhaps the plugin is not yet compatible with Kirby 4:

Oh yes, I have seen some commits regarding v4 updates but haven’t seen that issue. Thanks.