1. A method for populating a customized library of pattern templates, comprising: displaying a plurality of renderings of sample content in accordance with at least one markup language element, wherein each respective rendering of sample content corresponds to a pattern template comprising the respective at-least-one-markup-language element, and the plurality of renderings represents a master pattern template library; detecting a selection of a subset of the plurality of renderings that corresponds to a subset of the pattern templates; populating a customized pattern template library based on the selection; and displaying a representation of each pattern template in the customized pattern template library in connection with a user interface of a content editing tool.