api.SpeechSynthesisEvent - .utterance is not supported by iOS Safari

[12Me21]

What type of issue is this?

Incorrect support data (ex. Chrome says "86" but support was added in "40")

What information was incorrect, unhelpful, or incomplete?

compat data claims that SpeechSynthesisEvent's utterance property has been supported since iOS safari 7 (from ~2013), but this property doesn't exist

What browsers does this problem apply to, if applicable?

Safari

What did you expect to see?

No response

Did you test this? If so, how?

I've checked the properties of a SpeechSynthesisEvent instance on iOS Safari 15.5 (latest version), and it only has the following:

• Own keys:
  • isTrusted
• From SpeechSynthesisEvent.prototype:
  • constructor
  • charIndex
  • elapsedTime
  • name
  • @@toStringTag
• (as well as keys from Event.prototype and Object.prototype)

Can you link to any release notes, bugs, pull requests, or MDN pages related to this?

No response

Do you have anything more you want to share?

It also seems that iOS Safari doesn't have a SpeechSynthesis class, only the window.speechSynthesis instance, which has no .constructor and inherits from Object instead of EventTarget.
So, it's not possible to attach events to SpeechSynthesis, only SpeechSynthesisUtterance (which does inherit from EventTarget)

MDN URL

https://developer.mozilla.org/en-US/docs/Web/API/SpeechSynthesisEvent

MDN metadata

MDN page report details

• Query: api.SpeechSynthesisEvent
• Report started: 2022-07-07T06:47:39.905Z