I've been using FreeCAD 0.17 on Ubuntu 16.04 and everything was fine, but recently I have upgraded to Ubuntu 18.04 and when I start FreeCAD it freezes the all applications running for some seconds before the splash screen is displayed.
Apart from that it does work fine.
This is the version I am using:
OS: Ubuntu 18.04.1 LTS
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.17.13522 (Git) AppImage
Build type: None
Python version: 2.7.6
Qt version: 4.8.6
Coin version: 4.0.0a
OCC version: 7.2.0
Locale: English/UnitedKingdom (en_GB)