Steps to reproduce:
1.Open a page with VE
2.Add a reference
Uncaught TypeError: Cannot read property 'keyedNodes' of undefined appears in the console and VE gets unresponsive
See the screenshot attached.
Test Environment: http://en.wikipedia.beta.wmflabs.org/
Browser: Chrome Version 26.0.1410.65
OS: MAC OS X 10. 8. 5