Font problem with LyX 2.1.3 on Ubuntu 14.04

[Vinh Le Ngoc]

Hi,

I installed LyX 2.1.3 via the PPA last night and I'm having a problem where
previews and exports do not use the font selected in document settings;
rather, it always uses nasty bitmapped Computer Modern.

I've tried different combinations of fonts and even tried reinstalling LyX
to no avail.

Thanks,
Vinh