- uses a regular expression to identify the widgets already converted (using XML parsing is slower and more complicated)
- replaces automatic old <menulist...><menupopup type="select-*"/></menulist> with <select type="select-*" .../> to not build support for that into web-component code
- currently only box and button are converted, as converting v/hbox gives a JavaScript error with nextmatch headers (seems a problem with the children)
- caching is currently also disabled, as you would need to clear the filesystem-cache, when you modify the list of supported widgets (browser cache needs to be cleared!)