Knockout-Lite/app/BbCode/Tag/Strikethrough.php

<?php

namespace App\BbCode\Tag;

use Knockout\BbCode\Tag\SimpleTag;

class Strikethrough extends SimpleTag
{

    public function getCloseHtmlTag(): string
    {
        return '</s>';
    }

    public function getOpenHtmlTag(): string
    {
        return '<s>';
    }

    public function getTag() : string
    {
        return 's';
    }
}