The following datadef form elements are are reused in many places in the 2015 templates when links are to be included in the page content:

Datadef element	Description
... > Link > Type	Identifies the link as either internal or external. Internal links point to pages and assets within the same Cascade Site. External links point to locations elsewhere on the web.
... > Link > Link destination	Defines the link destination. If 'Type' (above) is set to 'internal', the datadef presents an asset chooser to select your desired link destination. If 'Type' is set to 'external', a text field is presented in which you provide the full URL to your desired destination. Note that this URL must include the protocol prefix ('http://', 'https://') to properly form the link.
... > Link > Open link in	Indicated whether the link destination should open in the same window/tab or a new window/tab. In most cases, 'same window' is preferred; please give careful consideration to user experience when selecting 'new window'.
... > Link > Auto-generate link text	Only appears when 'Type' is set to 'internal'. This option instruction the templates to use the linked page's title as the link text. If you are linking to something other than a web page (e.g., an image, pdf, etc.), this option should be set to 'no'.

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