Can't run Editor

After installing the latest version (today). and xulrunner,
I can’t get the editor working.
I mean, as soon as I click on the “design” tab, I get the error message ‘could not open design view’

I know it’s experimental but it look strange (I just tried to open the default class generated after initiliazing the project which contains only a label : “Hello vaadin user”.

Maybe it’s a xulrunner version problem ? which version would you recommend me, or where can I look to have more precisions about the error ?


I think I found the problem :
In fact, I tried to open the “visual editor” on the main class (the entry point), which must not be ‘editable’ with the visual editor

When I create a customComponent, the design view of the editor appears with no error…