From The Wall Street Journal:
The Polite Type has been developed in close collaboration with a diverse team with wide-ranging backgrounds in anti-racism work, gender research and D&I consulting. Additionally, the initial vocabulary for the font have been co-created with high-school-aged teenagers and youth from diverse backgrounds in Finland, together with The Children and Youth Foundation. . . . The font is an OpenType font file (OTF) that recognises a number of either discriminative and/or offensive English-language words. After typing the word, the font substitutes it with a more neutral, inoffensive word. . . .
The blur is an integrated part of the design for the words that have no literal translation, or their meaning is too broad to replace with just one word or their purpose is only that of hurting someone. Blurring is commonly used as a way to censor or to hide something offensive, but it has never before been used as a symbol in a font. . . .
The library of words deemed hurtful has been put together in collaboration with people from different origins, religions, world views and sexual orientations. Naturally, the library is always changing with the language itself.
Link to the rest at The Wall Street Journal (Sorry if you encounter a paywall)