I’ll spoiler-box this for the sake of being ultra-cautious, though it matters not at all to the plot and is not a material detail. In the third chapter of the new Harry Potter book, it says:
“The misty fug his breath had left on the window sparkled in the orange glare of the streetlamp ouside…”
Essentially, I just want to make sure that “fug” is a typo for “fog” and not some sort of British slang. I know I’m being silly; after all, why would there ever be such a stupid bit of slang? But I just wanted to make sure, because I can’t imagine this book hasn’t been proofread within an inch of its life. Not that it would matter in any material way if it were slang, but I’m a compulsive nut. Would any British people like to humor my freakish need to know?