Also, NoScript users will need to allow zidilife.com to view the article at all (a domain-specific authorization will not enable the popup though).
Focusing on one of the input fields and hitting 'escape' worked for me...
Touché. When clicking outside of the popup didn't work and I couldn't find a close button I thought maybe it's a new freemium-ish way to get subscribers. Vimium also highlighted the missing link.