Vaadin Custom Component Design view disappears after closing the tab in Ecl

I have a bizzare problem. The design view option for a custom component disappears after closing the tab of custom component in Eclipse. Is it a noted problem or is there a workaround?

I am using Vaadin-7 with Eclipse Kepler.

Could it be that your Eclipse somehow reverts to the default Java editor for the file. Although it should remember the setting by file, perhaps e.g. some other Eclipse plug-in resets it. Try selecting Open With… → Vaadin Editor in the context menu for the file.