Is it compaining about fonts or the fact that you're not running it in a real TTY? (Or a terminal emulator with framebuffer; I believe Terminology has it.)
In xfce4-terminal:
$ fbi screenshot-xfwm-compositing-settings-20140908-fs8.png
using "DejaVu Sans Mono-16", pixelsize=16.67 file=/usr/share/fonts/truetype/dejavu/DejaVuSansMono.ttf
ioctl VT_GETSTATE: Inappropriate ioctl for device (not a linux console?)
In tty1:
$ fbi screenshot-xfwm-compositing-settings-20140908-fs8.png
using "DejaVu Sans Mono-16", pixelsize=16.67 file=/usr/share/fonts/truetype/dejavu/DejaVuSansMono.ttf
map: vt01 => fb0
(You can only see that after you close the program.)
Edit: I just noticed the Netsurf framebuffer version is available in the package netsurf-fb. I'll give it a try sometime.