To avoid update two codes and styles, we should try to use existing keyboard in LockScreen. The possible code path is: 1. LockScreenWindowManager know now should show the keyboard on LockScreen 2. Fire system-resize to resize the active LockScreenWindow 3. Stop the event propagation 4. The LockScreenWindow get resized to show the keyboard frame The OOM issue should be considered, to avoid leaking information while the passcode shows.

Some follow-ups: 1. Experimentation: I added a <input type="text"> to lockscreen without changing JS codes and allowed keyboard to have higher z-index than lockscreen. On input's receiving/losing focus, The keyboard and input management seemed to behave quite well and as normally as we'd expect [1]. 2. According to bug 1060193 comment 1, in Settings app's Lockscreen passcode panel, what we see as apparently receiving inputs are actually <span>s, and there is a hidden input there to take keyboard inputs. We probably can copy-cat this model in Lockscreen. 3. We'd also need to consider how we're going to overlay "Emergency Call" key and "Cancel" key and have them behave expectedly. Overlaying "Cancel" is trickier as it can visually collide with backspace key on the keyboard. [1] this was two weeks ago; ongoing Lockscreen features/refactoring works may have changed things. By the way, do we really want to resize the lockscreen window? (if we just want correct z positions maybe just messing around with CSS would be easier).

Firefox OS is not being worked on