Copy-paste
character:
A placeholder character, usually represented by an
empty box or a box with diagonal crosses. This is displayed when either:
1. The character does not exist in your preferred character set (usually Unicode)
2. You used a font that supports a
different character set than your preferred one
3. (Linux and BSD only) You forgot to install the pango X11 library and ¯\_(ツ)_/¯ breaks on your display.