Tags composed of two words

[exeldoc]

Here the answer:

Tags without spaces and critical characters

@exeldoc In any case, for special characters you have to urlencode() your tags when creating the link and urldecode() it again before filtering. if($tag = urldecode(param('tag'))) { and href="<?= url('Arbeiten', ['params' => ['tag' => urlencode($tag)]]) ?>"

And it worked. Thanks!