Test passes if the text is spaced (or not) as you would expect [exploratory test].
Use the slider to adjust the width of the box.

Set font size  36px
Change the font to

ນັບທັງປະເທດຂອງຕົນດ້ວຍ ແລະ ກັບຄືນມາໃນປະເທດຂອງຕົນໄດ້.
specific test for ຫມ break: ກັບຊິມີເຄື່ອງຫມາຍ
Add your own test:

Default has no styling.

Set line-break to

Set word-break to