It's likely that "ft" was a ligature in the original which didn't survive the co...

		ink_13 on April 27, 2021 \| parent \| context \| favorite \| on: Calibre – E-Book Management It's likely that "ft" was a ligature in the original which didn't survive the conversion (for example, if the destination font doesn't have the character ﬅ). Sounds like a bug, though.