I want to use the Youtube add on, so after installing it with maven I started widgetset compilation and it seems to went through successfully. In VAADIN/widgetsets directory I have youtubeplayer.js, swfobject, in Widgetset.gwt.xml following lines have been added:
But when I open the window with embedded player, I get error messages that the widgetset does not contain implementation for org.vaadin.youtubeplayer.YouTubePlayer. I should recompile the widgetset.