Flexible columns were designed to make content management at the page-level easier for content creators. When a flexible column is added to a HubSpot page template, users will be given the option, within the content editor interface, to add, remove, and re-order modules, at the page-level. This feature allows designers to create fewer templates, while still allowing marketers the flexibility to customize each page to fit their needs.
Please note that there is no option to make flexible columns within blog templates or email templates.
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