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Link to "Make an Existing Landing Page Template Mobile Compatible" contains no info.
The January release includes the ability to create mobile-friendly landing pages. Within the resource document, it states " Caution: The landing page template may need to be upgraded. If you see that message, quickly read about how to Make an Existing Landing Page Template Mobile Compatible." Clicking on that link takes me to a blank page: https://docs.marketo.com/display/DOCS/Make+an+Existing+Landing+Page+Template+Mobile+Compatible