Debian currently packages the FLTK library as libfltk1.3 (version 1.3.4) but the FLTK developers (fltk.org) have released version 1.3.5 (stable) on March 3, 2019. Why is Debian (even testing and unstable) still using the old 1.3.4 version?
https://packages.debian.org/search?keywords=fltk
