cursor location wrong with smaller fonts

[tjaalton]

Some smaller font sizes cause the cursor on terminal and/or the preview overlay to be offset by a character or some. Happens on both N9 and Jolla:

N9:
121x34 OK
141x36 the cursor is off to the left by 1..N characters (gets worse when you type)
141x39 the cursor is off to the right by 2..N characters (gets worse when you type)
Jolla:
106x29 OK
119x33 the preview overlay cursor is off to the left by 1..N characters (gets worse when you type)
119x35 the preview overlay cursor is off to the right by 0..N characters (gets worse when you type)
136x41 the preview overlay cursor is off to the right by 2..N characters (gets worse when you type)
159x48 OK