Creates a compact font that renders all codepoints as tofu, inspired by github.com/adobe-fonts/adobe-notdef, which offers a more detailed explanation.
$ build.sh --version_major=1 --version_minor=0
$ ttx -l tofu.ttf
Listing table info for "tofu.ttf":
tag checksum length offset
---- ---------- -------- --------
OS/2 0x45A74D7F 96 296
cmap 0x002D00CA 88 400
glyf 0x3BC4E76A 44 496
head 0x1FDB682C 54 172
hhea 0x064201C4 36 228
hmtx 0x028A0000 6 392
loca 0x00160000 6 488
maxp 0x0004000C 32 264
name 0xEA124F09 327 540
post 0x00030000 32 868