No ticket. The earliest reference to the "new features" are in the last paragraph in original TODO file in the gropdf directory. I think they are all done (or irrelevent) now, only took me 10+ years! A new TODO would contain the aspiration to handle ttf/otf/woff fonts natively in groff. The microsoft spec for ttf is a mere 3030 page pdf and the ISO-OpenType spec is another 640 pages, so perhaps a bit more than a weekend's hacking! And then gropdf, as I originally planned it, will be complete.

This is fine, but it should wait until gropdf has been cherry picked from my branch to master, when Branden is ready. I hope I won't have to maintain two different versions for long, for example, Colin Watson's reproducible build patch would not apply against the new gropdf, I had to roll my own.

Email discussion at http://lists.gnu.org/r/groff/2023-06/msg00174.html and other links in the thread

Here's Werner's original deprecation notice.

67d234991b NEWS    (Werner LEMBERG      2003-02-14 11:30:13 +0000  922)   \D'f ...' is deprecated since it depends on the horizontal resolution of
67d234991b NEWS    (Werner LEMBERG      2003-02-14 11:30:13 +0000  923)   the output device (given with the `hor' parameter in the DESC file).
87edb52555 NEWS    (Werner LEMBERG      2003-03-10 21:51:55 +0000  924)   Use the new \D'Fg ...' escape instead.

groff 1.19 was released on about 2003-04-28, so presumably the one or two people who read the NEWS file noticed this then.

diff --git a/src/libs/libdriver/input.cpp b/src/libs/libdriver/input.cpp
index 821b526bd..97d90d291 100644
--- a/src/libs/libdriver/input.cpp
+++ b/src/libs/libdriver/input.cpp
@@ -1361,6 +1361,7 @@ parse_D_command()
     }
   case 'f':                    // Df: set fill gray; obsoleted by DFg
     {
+      error("'f' drawing command is obsolete; use 'Fg' instead");
       IntArg arg = get_integer_arg();
       if ((arg >= 0) && (arg <= 1000)) {
        // convert arg and treat it like DFg
diff --git a/src/roff/troff/input.cpp b/src/roff/troff/input.cpp
index e797e2200..cc0b59f38 100644
--- a/src/roff/troff/input.cpp
+++ b/src/roff/troff/input.cpp
@@ -8754,6 +8754,9 @@ static node *read_draw_node()
            error("even number of arguments needed for spline");
          break;
        case 'f':
+         error("'f' drawing command is obsolete;"
+               " use 'Fg' drawing command, 'M' escape sequence,"
+               " or 'fcolor' request instead");
          if (npoints != 1 || !no_last_v) {
            error("one argument needed for gray shade");
            npoints = 1;