Dear Jeremy, I'm an upstream of some of the software that depends on lablgtk2. Porting to GTK+3 is not an easy option, since lablgtk3 does not exist (and will not exist as far as I know).
As far as I understand, the main offender here is libgnomecanvas2-0. I was wandering if we could rebuild lablgtk2 switching off support for some gnome technology: that is get rid of the binary package liblablgtk2-gnome-ocaml but keep the others) Lablgtk2 is made of optional components that can be switched off at configure time. Eg on my system I currently get: LablGTK configuration: GtkGLArea yes libglade yes librsvg yes libgnomecanvas yes libgnomeui yes libpanelapplet not found gtkspell yes gtksourceview 1 not found gtksourceview 2 yes quartz not found If it is a viable option for you, can you tell me which of the above are going to be a problem for Buster (in addition to libgnomecanvas)? Best -- Enrico Tassi