Purging and reinstalling Blender didn't help. However listing installed packages shows minor version discrepancy.
blender-data/testing,testing,now 2.79.b+dfsg0-4 all [installed,automatic] blender/testing,now 2.79.b+dfsg0-4+b2 amd64 [installed] Not sure if this can be the reason but I am reporting it anyway. -- Mladen Mijatov Key ID: 4096R/83EFD5A0 2013-08-18