Firefox in iOS is difficult to use to edit existing text, e.g. a Wikipedia article. The problem is that when the user taps to place the cursor, the editor moves the focused line to the bottom of the editor window. This makes it nearly impossible to accurately select a range of text unless it is very short because the following lines are hidden. Also, the bottom handle of the text selection (for dragging to extend the selection) is too close to the bottom of the window, making things unnecessarily tricky. Dragging down usually causes many lines of text to scroll past too quickly for an accurate selection. The solution is to put the focused line in the middle of the editor window, a common practice.
