Grabbed dndbeyond's source code

```
~/go/bin/sourcemapper -output ddb -jsurl https://media.dndbeyond.com/character-app/static/js/main.90aa78c5.js
```

ddb_main/node_modules/hyphenate-style-name/index.js

@@ -0,0 +1,19 @@
+/* eslint-disable no-var, prefer-template */
+var uppercasePattern = /[A-Z]/g
+var msPattern = /^ms-/
+var cache = {}
+
+function toHyphenLower(match) {
+  return '-' + match.toLowerCase()
+}
+
+function hyphenateStyleName(name) {
+  if (cache.hasOwnProperty(name)) {
+    return cache[name]
+  }
+
+  var hName = name.replace(uppercasePattern, toHyphenLower)
+  return (cache[name] = msPattern.test(hName) ? '-' + hName : hName)
+}
+
+export default hyphenateStyleName