The JavaScript plugin is used to run server side JavaScript snippets.

At this time it is only used to determine what layout / theme to use. The layout name is defined in a script written in JavaScript.

We are likely to fade this plugin out because we now have our own snap_expr class which is easier to use and faster and integrated with our signal system. Also it looks like we would not need the full power of JavaScript when we can just use a C++-like expression as offered by snap_expr.