Delete route can cause eclipse to hang when clicking outline / design mode

I created a new fuse project (using spring archetype).
I opended the xml file, switched to source view, removed the route, so there is just a empty <camelContext></camelContext> in the XML.
switched back to design view.

The screen is then grey. But the old outline of the route is there. As weel a piece of the zoom. See screenshot.
I then clicked on the Outline heading, and then clicked on the Task List heading.

Now Eclipse hangs, with a spinning ball (Mac)