Regression: Chrome: <Enter> key doesn't work

Cause is unknown. Can't reproduce it deterministically, but it happens regularly when working with Chrome

Symptoms:

• Edit a document
• In the summary field, try to type several lines (with Enter)
  Expected: Newlines are added
  Actual: Javascript errors occur. NO newline is added
  OR:
• Log in to CMS
• Go to the documents
• In the search box, enter a search query
• Hit <Enter>
  Expected: The search is done
  Acual: Javascript errors occur.

Only in Chrome (not Firefox, IE8 or IE9)

The errors:

Uncaught TypeError: Cannot call method 'click' of null
shortcut.add.disable_in_input
func http://cms.demo.test.onehippo.com/:182

POST http://cms.demo.test.onehippo.com/?wicket:interface=:1:dialog:content:form:buttons:0:button::IActivePageBehaviorListener:0:-1&wicket:ignoreIfNotActive=true&random=0.5212482565548271 500 (Internal Server Error) wicket-ajax.js:666
Wicket.Ajax.Request.doPost wicket-ajax.js:666
(anonymous function) wicket-ajax.js:642
Wicket.Channel.schedule wicket-ajax.js:437
Wicket.ChannelManager.schedule wicket-ajax.js:475
Wicket.Ajax.Request.post wicket-ajax.js:642
Wicket.Ajax.Call.submitForm wicket-ajax.js:805
Wicket.Ajax.Call.submitFormById wicket-ajax.js:785
wicketSubmitFormById wicket-ajax.js:1546
onclick http://cms.demo.test.onehippo.com/:1
shortcut.add.disable_in_input
func http://cms.demo.test.onehippo.com/:182