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Add the widget to a specific page on a Refined site
Paste the code into an HTML module in the page’s Layout Editor.
Add the widget to an entire Refined site
Go to the Refined Administration.
Click Sites in the left-hand menu.
Pick the site you want to add the widget to.
Go to the Configuration tab > Advanced Settings > Activate Custom HTML.
Paste your code in the At the end of BODY field.