The commenter was actually very considerate and raised a warning where it might be seen. And they were kind enough to attempt this with two different browsers. After that you can buy my troubleshooting time at its usual hourly rate.
(Because it's a frequent enough issue: I wouldn't see that warning as being about a one-off obscure bug that will affect few people and doesn't matter. It's a warning that the web site probably did not enough take compatibility in consideration - and was approved without such consideration.)
"Runs fine for me" is an absurd bar for reliability / compatibility, no?