on ubuntu 13.10 multiple hits on ctrl+tab makes my intellij 13 keyboard stuck (no key works)

workaround try this when it happens:

ibus-daemon -rd

http://youtrack.jetbrains.com/issue/IDEA-115661

http://youtrack.jetbrains.com/issue/IDEA-78860

Restarting ibus-deamon may cause issues with other applications¹ or even crash IntelliJ, according to IDEA-78860. However it also suggests there are 2 alternate solutions:

• Disabling IBUS support for idea. This is done with an empty XMODIFIERS environment variable when starting IntelliJ. For example, add this at the beginning of idea.sh and restart IntelliJ:

  # workaround for https://youtrack.jetbrains.com/issue/IDEA-78860
  export XMODIFIERS=
  

• Force IBUS to keep the order of events by setting IBUS_ENABLE_SYNC_MODE=1 for ibus-daemon². In my case I implemented it by adding the following to my ~/.xsessionrc (create the file if it does not exist) and restart my session:

  # workaround for https://youtrack.jetbrains.com/issue/IDEA-78860
  export IBUS_ENABLE_SYNC_MODE=1
  

(I actually did both so I don't know which one fixes it for me)

If this works for you, this has the advantage of fixing the problem once and for all, and you shouldn't have to restart ibus-daemon any more.

The only inconvenient is that you need to restart IntelliJ or even your whole session to apply it the first time.

¹ _{In my case dead keys didn't work any more afterwards in some applications like Skype.}
² _{Apparently IBUS should have the sync mode enabled by default in a future release, see issue 1697 and the corresponding commit.}