The bug is yours: non-ascii apostrophes.
wget https://codeberg.org/kitten/app/raw/branch/parameter-objects/examples/markdown-preview/index.page.js
grep -E "Interestingly|updates while|sends a" index.page.js |od -c
0000040 342 200 231 s v a l u e h a s n
...
0000140 w , I 342 200 231 m g o i n g t
...
0000300 w e d o n 342 200 231 t w a n t
En.Wikipedia doesn 342 200 231 t want non-ascii apostrophes either [1] ;).