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I can't add my custom css in cms->page->design->layout, my code enter image description here

  <css src="Magento_Theme::css/mycss.css" /> 
<referenceContainer name="content"> 
    <container name="home-page-full-block" htmlTag="div" htmlClass="home-page-full-block">  
      <block class="Magento\Framework\View\Element\Template" name="homepage_block" template="Magento_Theme::mypage/my_home_page.phtml"></block>

marked as duplicate by Amit Bera May 9 '18 at 8:22

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

  • show your CSS file path. – Suresh Chikani May 9 '18 at 7:36
  • /home/root/www/pub/static/frontend/Developer/shop/en_US/css/mycss.css – Ashik Ali S May 9 '18 at 7:50
  • <head> cannot be support by layout update xml at magento2 – Amit Bera May 9 '18 at 8:19

This is a known bug in Magento 2. The fix for this was planned for the 2.2.4 release. But is know scheduled for the 2.3.0 release. For now this will not work.

further information: check this link

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