Does @readium/navigator (web) support TTS/read-aloud, or do we need to implement it ourselves?

I'm building an EPUB reader using the Readium TypeScript toolkit (@readium/navigator ^2.3.0) and trying to enable read-aloud / TTS for reflowable EPUB text.

I searched through the package types and docs but couldn’t find anything related to TTS:

no readAloud, tts, or speech config

EpubPreferences only handles fonts/layout

the only audio-related thing I found is WebAudioEngine, which seems meant for audiobooks, not TTS for EPUB text.

So I’m trying to confirm the intended approach.

Questions:

Does @readium/navigator (web) actually provide any built-in TTS/read-aloud support that I might be missing?

If not, is the typical approach to implement TTS using the Web Speech API (window.speechSynthesis) and extract text from the navigator iframe DOM?

Thanks!