Icons in Lyx

[UD]

Is there a way to make the icons in the Lyx tool bar larger?  Mine are TINY and nearly invisible. I am using Lyx 2.2 under Lubuntu 16.04 with a Cinnamon 2.8 desktop on a Yoga 2 Pro with HiDPI (3200X1800 pixels). Thanks, Ehud Kaplan