[app]

This caused a bunch of headaches at Vimeo while working on our iframe embed code a couple months back. If I remember correctly Safari (and now I believe Chrome 10) will not send cookies in iframe POSTs unless a user specifically navigates in that iframe. So for example clicking the "like" button in a Vimeo video wouldn't work right away. There is a workaround: you programmatically fake a POST right away, and the second POST works because the user has interacted with it.

This might be a nice "headache" for marketers, but there are legit uses. As a developer I'd prefer if browsers were consistent in their default handling of cookies.

[joebananas]

Perhaps you guys should have taken this as a sign that Vimeo relys way too much on cookies. You can't even search the site if you don't accept cookies, no other site I've used fails that way.