Yes, but there is more than that there. What if I as the client try to print a page or export to PDF. I think that there is nothing sensitive visible on the pag

Yes, but there is more than that there. What if I as the client try to print a page or export to PDF. I think that there is nothing sensitive visible on the page so I share the result. It turns out that there was actually sensitive info in the canvas that was not visible due to something like overdraw. As a simple example imagine that an image is drawn to the canvas and then blacked out. You wouldn't expect that the saved PDF may contain those as separate layers. Of course this highlights an existing issue with complex formats. You need to be very careful before sharing complex documents.