Last modified: 2012-11-29 12:43:19 UTC
When the error tooltip is shown for Label, Description or Aliases, the toolbar remains disabled. Cause of this it's not possible to leave the edit mode without reloading the site.
It seems https://gerrit.wikimedia.org/r/#/c/27122/ fixes this issue. Needs further investigation though.
Verified in Wikidata demo time for sprint 18