I've reproduce the situation with whole eclipse crash without clear message what was a reason: after debug I've find the reason: it was java.lang.NoClassDefFoundError in the function VpeTemplateSafeWrapper ->
public VpeCreationData create(VpePageContext pageContext, Node sourceNode, nsIDOMDocument visualDocument) {
return delegate.create(pageContext, sourceNode, visualDocument);
}
it look like you should handle this situation also - so I reopen the issue.

you are catch only Exception VpeTemplateSafeWrapper and in VpeTemplateSafeWrapper.create catch Exception on more high level - it look like you should also catch Throwable? and somehow handle Throwable in VpeTemplateSafeWrapper.create?

reference to initial issue:
https://issues.jboss.org/browse/JBIDE-9339