This is called font substitution, and it's ultimately controlled by fontconfig. I assume that Specimen is using normal GNOME text-rendering functions and just passing it the chosen font. A character not present gets automatically substituted with some other font. That's what should happen for most purposes—but it makes no sense for a font viewer.
** Also affects: gnome-specimen Importance: Undecided Status: New -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/253616 Title: Displays characters from different font when font doesn't contain it To manage notifications about this bug go to: https://bugs.launchpad.net/gnome-specimen/+bug/253616/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs