title: sql developer hangs on startup - what can I do?
body: <p>At present I cannot run it (SQL Developer 4.1) because it hangs on "Restoring Editors" while starting. I suppose I've done it by exiting it before by killing sql developer process because it was hanged on fetching objects to Schema Browser so long...
  Maybe I would clean some temporary files but can't find any.
  Any ideas?</p>