Editor.getSymbols

This function returns the array of symbols currently in use in "Insert Character" menu.

It's main purpose is to allow developers to extend the Xopus default symbols by merging the array returned by this function with your own, and supplying Editor.setSymbols() with the resulting array:

Editor.setSymbols(null);
var base = Editor.getSymbols();
extended = base.concat(["a", "b", "c"]);
Editor.setSymbols(extended);