When XSLT 2.0 functions (xsl:function) with similar names and the same namespace prefix have been defined and used in a stylesheet, Stylus Studio occasionally changes function names in value-of clauses, when switching back from the mapper to the source editor. If these functions have a different number of parameters, I am at least getting an error. Still this behavior is not particularly funny. Source code not altered by graphical actions should not be changed at all by switching from mapper to source editor (also see today's post line break variable destroyed).