Balsa currently uses the Gnome printing libraries to print a message;
these are "heading towards planned deprecation"[1], so we should head
towards a plan to move to GtkPrint. We should plan for that move
anyway, as it gives much better control of printing.
But...to print html message parts, Balsa must be built with gtkhtml3,
which uses the Gnome libraries. So unless/until gtkhtml3 is ported to
GtkPrint, we have the options:
1. Stick with Gnome printing and keep the ability to print html
parts;
2. Move to GtkPrint and lose the ability to print html parts;
3. I don't see a third option.