How to render text including video embed field
check_markup() is not able to handle attached metadata which some text filters need to work properly.
You have to use the render element processed_text:
$renderArray = [
  'content' =&gt; [
    '#type' =&gt; 'processed_text',
    '#text' =&gt; $node-&gt;field_html_containing_video_content-&gt;value,
    '#format' =&gt; $node-&gt;field_html_containing_video_content-&gt;format,
  ],
];

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