• I have tried restarting my IDE and the issue persists.
• I have updated to the latest version of the packages.
• I have read the FAQ and my problem is not listed.

Repro

{
  "rules": {
    "@typescript-eslint/unbound-method": "error"
  }
}

const collator = new Intl.Collator("en")
const sorted = ["foo", "bar"].sort(collator.compare)

(tsconfig not included as the same issue occurs regardless of config)

Expected Result

No error, as Intl.Collator.compare is a native bound method intended to be used this way.

Actual Result

2:36  error  Avoid referencing unbound methods which may cause unintentional scoping of `this`.
If your function does not access `this`, you can annotate it with `this: void`, or consider using an arrow function instead  @typescript-eslint/unbound-method

Additional Info

The rule's source code does account for builtins, but it looks like only top-level bound methods are put on the list to ignore when checking. So Intl.Collator itself is ignored, but Intl.Collator.compare isn't because it's another level down. Presumably the same issue affects other similar methods like Intl.DateFormat.format as well -- maybe check the Intl constructors individually when generating the ignore list?

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