For missing glyphs, I think the question mark '?' is a poor choice since it already conveys meaning in language, and doesn't make it obvious that the issue at hand is a missing glyph.
A better replacement (if it's present in the game's fonts) could be something like □, which is often used in other software to represent missing glyphs.
What made me suggest this is that I often accidentally type "gl" into the chat with another keyboard layout, which sends a message that looks like "??". This often makes the other person think that I am confused or mad, which is not the intention at all.
For missing glyphs, I think the question mark '?' is a poor choice since it already conveys meaning in language, and doesn't make it obvious that the issue at hand is a missing glyph.
A better replacement (if it's present in the game's fonts) could be something like □, which is often used in other software to represent missing glyphs.
What made me suggest this is that I often accidentally type "gl" into the chat with another keyboard layout, which sends a message that looks like "??". This often makes the other person think that I am confused or mad, which is not the intention at all.