Broken references in Web Audio API

[dontcallmedom-bot]

While crawling Web Audio API, the following links to other specifications were detected as pointing to non-existing anchors, which should be fixed:

• [ ] https://heycam.github.io/webidl/#dfn-get-buffer-source-reference
• [ ] https://webidl.spec.whatwg.org/#dfn-present

_{This issue was detected and reported semi-automatically by Strudy based on data collected in webref.}

[padenot]

@dontcallmedom just a note here to say that the first link is indeed preset in the spec, but in <del> tags, and the modification has already been made. How should we proceed in those cases?

The second case has a PR.