How can I change the multiline for c3js bar chart x axis tick text in normal horizontal mode?

in normal horizontal mode, multiline is not working and how can I fix?
As I noticed if included > rotate: 90, multiline is not working. but not okay to show without rotate because most of the tick values are long.
data: { x: 'x', columns: columns, type: 'bar', labels: true }, axis: { x: { type: 'category', tick: { rotate: 90, multiline: true } , height: heightForX },

multiline is correctly displayed in vertical mode.
axis: { rotated: true, x: { type: 'category', label: { text: labelY, position: 'outer-middle' } , tick: { multiline: true, } } },

but cs3j sample, multiline is working with rotate mode
https://c3js.org/samples/axes_x_tick_rotate.html