IDL/dfn of terms with underscores not autolinking as expected

[inexorabletash]

When needing to use underscores to escape IDL keywords, the docs seemingly indicate this should work:

<xmp class=idl>
interface Foo {
  void _bar(any x);
};
</xmp>

The <dfn method for=Foo>bar(|x|)</dfn> method...

... but I'm seeing the IDL fragment define a #dom-foo-_bar id rather than autolinking to the #dom-idbkeyrange-includes id defined by the prose.

[inexorabletash]

I was able to work around with:

The <dfn method for=Foo lt="_bar(x)|bar(x)">bar(|x|)</dfn> method...