Dear Xzgv maintainer,

Xzgv does not show PBM files if they don't have a comment. This
is wrong. Comments are not mandatory according to pbm(5) and
Netpbm programs like pnmdepth or pnmflip neither require nor
produce any.

Sample PNM files along with the shell script to create them are
available from :

http://www.teaser.fr/~amajorel/bugs/pnm-comments/

Thanks in advance.