Unicode ligatures: not all software does normalised search forgetting ffi 

Via a private share, I found out that some software forgets to perform a Unicode normalisation when doing a search.

That means that ligatures do not match the non-ligatures in for instance these words:

• “ff” and “ff”, as in “difference” versus “difference”
• “fi” and “fi” as in “notification” versus “notification”.

For more information, read [WayBack] Unicode equivalence – Wikipedia and make sure you know about these normal forms:

NFD Normalization Form Canonical Decomposition	Characters are decomposed by canonical equivalence, and multiple combining characters are arranged in a specific order.
NFC Normalization Form Canonical Composition	Characters are decomposed and then recomposed by canonical equivalence.
NFKD Normalization Form Compatibility Decomposition	Characters are decomposed by compatibility, and multiple combining characters are arranged in a specific order.
NFKC Normalization Form Compatibility Composition	Characters are decomposed by compatibility, then recomposed by canonical equivalence.

–jeroen