[jer0me]

Yes. This site seems to be using https://krpano.com, but https://openseadragon.github.io/ is an open-source alternative. The New York Times has used the latter for features like this one: https://www.nytimes.com/interactive/2025/04/26/world/europe/...

[gblargg]

Props to them for not locking out older browsers as many sites are doing these days.