Created attachment 174058 [details]
Minimal example of this bug
A dynamically created button won't display in some circumstances.
1) Make a page similar to the minimal example attached. Click TEST.
2) After the input area is displayed, some work is done (the setTimeout does the same effect).
3) Instead of showing the button after some time, the button disappears until the window is resized, form element is clicked, or (in Android) after zooming.
It seems to be a bug in the layout, when the button disappears the inspector shows it to be at the left of the screen.