Error after upgrading

My application works fine using vaadin 7.4.2 (both in Eclipse and when i deploy it to the server).

If i change the vaadin version (simply updating my pom.xml), it stops working, throwing the nasty:

Failed to load the bootstrap javascript: ./VAADIN/vaadinBootstrap.js?v=8.0.1

This happends whether i use version 7.6 or 8…

Why would this happen if the environment hasn’t changed?


If anyone is interested, this solves it and should be more widley known:-