Seems to work well when it's searching the PDF text layer as ligatures are a font rendering effect. You're right — ligatures are not as common in modern books.

Seems to work well when it's searching the PDF text layer as ligatures are a font rendering effect. You're right — ligatures are not as common in modern books. Might be iffier in OCR mode: it seems to use Tesseract, which is known to have issues recognising ligatured text.