FLOSS Manuals have been using the GPL for their manuals, which is a good licence if a strange choice for software manuals, but their latest manual, a digital art handbook, is licenced under Creative Commons’s Attribution Non-Commercial Share-Alike licence (NC-SA).
NC-SA is not a free licence by any definition. The FSF, OSI, Debian and Freedom Defined all reject it. It has no place in a project calling itself “FLOSS”.
It would be better for FLOSS Manuals not to publish this book than to break their principles in this way, particularly given the project’s robust rejection of the FDL for lesser reasons.
There are already other NC-SA Digital Art Textbooks available. What would be exciting, if it’s going to be CC licenced, would be a BY-SA one.
FLOSS Manuals should switch to BY-SA generally if the FDL is not acceptible. I’m not suggesting dual-licencing, which would just compound the problem, I’m suggesting re-licensing the project as a whole as BY-SA. This would answer FLOSS Manuals’ concerns about the FDL much better than using the NC.
But in the mean time, FLOSS Manuals should either relicence or pull the digital art manual. Because NC isn’t FLOSS.