Samsung tablet/ Android 4.0.4 steps to reproduce: 1. Load marketplace.allizom.org on your latest Firefox Nightly 2. Start the purchase of a paid app 3. Log in using Persona 4. Enter PIN 5. Confirm MT auth using your phone number 6. Enter Credit card info 7. Confirm purchase expected behavior: After purchase the 'Payment Complete!' screen closes and the user is prompted to install the app they just bought observed behavior: After purchase the 'Payment Complete!' screen never closes. If the user closes it to return to the app details page, user is shown the 'Payment Cancelled' error message after a successful purchase. I didn't see anything suspicious in the logcat.