Long string in source or target causing layout issue in editor. Seems like work-break not working properly for Firefox.
Fixed in 1.7. Tested with firefox 13, chrome 19. See https://github.com/zanata/zanata/commit/4d5d42fe3182332418fa372618b448b3d6ef84c2
Fixes also applied in 1.6.1
VERIFIED with: Zanata version 1.7-SNAPSHOT (20120702-0025) with Firefox 10.0.5 and Firefox 13.0 Zanata version Zanata version 1.6.1-SNAPSHOT (20120702-0014) with Firefox 10.0.5 and Firefox 13.0