That method isn't entirely reliable either: all come out at “question mark in a box” (Chrome, Edge) or “codepoint hex in box” (FF) on the old Win10 box that I'm currently trying to retire. The come out find on a similarly default Win11 setup.

While the issue here is Win10, it shows that the problem is client font sensitive so it might affect others too (perhaps those running old-but-still-supported Linux distro releases with default fonts).