The column-count CSS property describes the number of columns in an element.
The property which determines the size of an object on the Y-axis
Try with 1 column-count and as text get bigger than available height it will auto split in to second column - columns 1 150px
CSS columns vertical overflow workaround
The problem is that when there is some fixed height opera generates more columns than specified in column-count instead of adding scroll
Opera: column-count with max-height