XSLT stylesheets have the ability to import and include other stylesheets. This allows for a modular structure for the templates to be created. It also allows for easier maintenance. However, if one is working with a large project like the DocBook Projects stylesheets it can be difficult to remember the names and locations of all the stylesheets.
To this end, the XSLT editor provides content assistance for the href attribute. The scope of the assistance is restricted to the project that the current stylesheet that is being editted resides.