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The HTML module has to be manually enabled for it to become available in the Layout EditorPage Builder. Disabling the HTML module doesn't delete the HTML modules you added to your site, but hides them until you enable the HTML module again.
Go to the Refined Administration.
Select the site you want to work with.
Click the Configuration tab.
Under the Security heading, toggle Enable HTML module on.
Add this module to a page
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All Refined Pages, Jira Projects, and Confluence Spaces that you add in the Site Builder get their own landing page on your Refined site. Modules are the building blocks of these pages.
Go to a page’s Layout Editorthe Page Builder.
Hover your mouse over a spot in the layout the desired location on the page and click the + Add module button that appears.
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Go to the video on YouTube or Vimeo.
Click Share > Embed.
Copy the HTML and paste it into an HTML module in the Layout Editor Page Builder.