I use Feedburner to deliver RSS feeds on my blog, and I prefer delivering them as E-mail subscriptions, but for past few days, I have been noticing that people are subscribing to my RSS feeds using other feed readers, such as mozilla built-in feed reader. I want to disable this, is there a way I can detect the user agent of "Mozzila compatible Agent"'s user-agent and input it somewhere in feedburner to disable the non-email subscriptions on feedburner?
Basically, I don't want anything except e-mail subscription in below screenshot-