Also, it depends on PREFERENCE, which only one of us is aware of.
"American English" is pidgin English, so there's that.
The Associated Press Stylebook says the correct way to write the possessive case of Chris is Chris', not Chris's. Other style guides, including the Chicago Manual of Style, say Chris's is correct. If there isn't a specific guidebook you need to follow, you can use either Chris' or Chris's.Oct 10, 2022