Fix the naviguation buttons at the bottom of the screen (below the keyboard)

When you leave a group to the next one, if the first question of the group is a select_one the navigation buttons are at the bottom of the screen, if the next one begins with a text fields, those buttons are moving on the top of the keyboard.
This causes some surprises when you quickly skip optional groups of question.

I am not sure it would be possible to fix the position of the button at the bottom of the screen an when a text is asked, to put the keyboard over the navigation buttons.