Crash on "empty" image frame

[SnowBCrash.sbf.txt](https://github.com/user-attachments/files/25470893/SnowBCrash.sbf.txt)
SnowB crashes when trying to preview this font (change the .txt to just .sbf), it's supposed to be a space but I guess SnowB can't handle it like this.
<img width="817" height="107" alt="Image" src="https://github.com/user-attachments/assets/399c250a-1ffd-4636-88d8-2f400e516ac3" />