Sandbox check

Archived artwork runs in <iframe sandbox="allow-scripts"> with no allow-same-origin, which gives it an opaque origin — one that matches nothing, not even the server the files came from. Storage, cookies and workers are all keyed to an origin, so in that frame they throw rather than work, and a piece's own images taint any canvas they touch.

A shim restores them, and this page frames a document under the identical sandbox to check that it still does. Everything below should say pass in a current browser; a fail means some archived pieces are broken here, and which line failed says which ones.

Running…