How to fix post character instead of switched character to compatibility variant in Safari Browser.

safari-compatibility-variant-fix.md

Before

fetch(URL, {
  method: "POST",
  body: JSON.stringify({
    foo: bar
  }),
})

After

fetch(URL, {
  method: "POST",
  body: new TextEncoder("utf-8").encode(JSON.stringify({
    foo: bar
  })),
})

If the same problem persists, globally apply a font that does not treat the Unicode of the character in question as a compatible character too.