404. That’s an error.

The requested URL /bookmarks/mark?op=edit&bkmk=http%3A%2F%2Fdata.bnf.fr%2Ffr%2F15522001%2Fthe__ha__ho_%2F&title=Th%C3%AA%CC%81+Ha%CC%80+H%C3%B4%CC%80 was not found on this server. That’s all we know.