Within Teamwork Desk, you can enable Disqus on your Help Docs site to allow commenting.
To enable this, you will first need to set up a Disqus account.
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Once your account is set up, go to the Disqus Admin panel > Settings > and copy your shortname.
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To enable within Teamwork Desk, go to the Help Docs area of your site.
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Hover over the Help Docs site you wish to update and select Settings from the dropdown menu.
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Scroll to the Comments section at the bottom of the Settings area, where you can paste in
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You can then enable comments on an individual article basis. While editing an article, go to More Options in the right sidebar and toggle the Enable Comments option.
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Disqus will then be shown on your article for customers.
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For more information, see: Creating a Help Docs Article