What to click
Today I added a live bookmark to my firefox, I didn’t want it to be submitted to del.icio.us, but when I added the feed, I was asked the following question:

What should I click here? The icons tells me that the right one will submit the link to del.icio.us and the left one will cancel. This complies to the UI guidelines for Gnome. However, the text tells me the opposite.
I decided to press escape, since that always should work as cancel (enter works as continue/yes etc). However, in this case, cancel submitted the link.