From the jury’s reasoning:

The “Library of Lost Books” opens up a digital space that makes a part of German-Jewish history come alive that is almost never shown. It is therefore much more than an online archive. The focus is on the people at the Highter Institute for Jewish Studies in Berlin: their resistance, their solidarity, their modernity and enlightenment – and their library. […] The content presented is […] exceptional in its quality and significance, allowing a special insight into Jewish life, away from traditional and stereotypical ideas: examples include the first generation of professional librarians in Germany and the openness of the Higher Institute, where students could train to become rabbis, regardless of religion or gender. The special interactivity, the opportunity to go on a search for the lost books that were stolen by the Nazis or lost in the post-war period, captivates and involves users even more deeply in the history of this extraordinary place. Past and present connect and relate to each other – this citizen science project shows how Nazi injustice continues to have an impact in the present.

For the whole text (in German) see here:
https://www.grimme-online-award.de/2024/preistraeger/preistraeger-detail/d/library-of-lost-books-1

Have a look at the award ceremony here:
https://www.youtube.com/watch?v=AeF8mL8EAxw