This used to work always in 32 bit:
For other fonts as well. Now, when built for 64 bit, not a single of ALL fonts will return a non-nil value.
The docs do not mention that this isn't working any more.
And work-around suggestion?
My goal is to detect fonts that are latin/roman scripts. Or, in the end, I need to find mono-spaced fonts (which I currently do by comparing the StringWidth of various chars, and which will crash or become very slow if I include non-roman scripts such as cyrillic and japanese).