A "shared element" is any element that has been customized and then saved for later re-use on a different page or banner.
Site admins can drag and drop a shared element just like any stock, non-customized element; when the shared element is added to a page or banner, though, it will automatically retain the original customizations that were applied when it was first saved.
Creating shared elements
Start by adding an element to a page and customizing it. Open up the Element Settings window by clicking the “gear” icon at the upper-right corner of the element.
Click the "Share" toggle in the title bar of the Element Settings window.
Give the element a unique name that describes its contents or functions, then click "Save and Convert to Shared Element."
The new shared element will appear in the "Shared" section of the element library.
Editing shared elements
You can edit shared elements after creating them by going to Composer > Elements.
Click on an element to open it for further editing. Any edits you make to an element here will be applied to all instances of that element.
When you drop a shared element onto a page or banner, the usual “gear” icon will be replaced with a "Shared" flag, to let you know that this is a shared element.
Making a shared element unique
You can still edit shared elements that have been placed onto a page. When you click the "Shared" button, you'll be prompted to decide whether you want edit the saved shared element, or if you want to “orphan” the shared element you're currently working on. Select "Orphan and Edit" to work on this copy of the shared element in isolation; select "Edit Shared" to edit the master copy of the shared element.
After a Shared element has been orphaned, it will act like an independent, non-shared element.
Sharing Container elements
Container elements can be shared and reused on other pages. All elements inside the Container will be included when the shared Container is added to another page.
Unlike regular shared elements, shared Container elements cannot be orphaned. This means that shared Container elements can only be edited in the Shared Element editor.