Two things I really dislike(d) at my Java productivity booster IntelliJ IDEA from Jetbrains.
Incoming Network Connections Problem
This occurred frequently until I stumbled upon this YouTrack issue.
So the solution is (after – if needed – setting your time synchronization to auto preventing ‘timestamps differ by NN seconds – check your system clock’ error messages) to enter this command at the command line:
sudo codesign --force --deep --sign - /Applications/IntelliJ\ IDEA\ 14.app/
At least for me, the error never came back again.
Focus Lost Issues
This issue seems to becoming an evergreen, see the YouTrack issue.
In short: When starting IDEA, it claims again and again the focus, even if you switched to another desktop (on OS X).