Try setting your browser to desktop mode instead of mobile via the settings in IE. Some boards seem to work fine in mobile mode and some don't.
Same happens here but there is a knack to getting the keyboard to stay on screen. I did it just now to write this post.
It's basically a timed double tap. First tap to initiate the keyboard, and as soon as u see it pop up from the bottom of the screen just tap again in the textbox. Takes a bit of getting used to but you will get a feel for it once u try.
Discovered this fix by pure frustration when tapping the box frantically in rage.
