Chrome OS doesn't have "native" Text-To-Speech. Since last Dev Update, it includes a built-in component extension that provides speech synthesis powered by Native Client technology. 

You can dive into this extension by opening a new tab to

If you want even more fun, feel free to dive into Google Text-to-speech component extension for Chrome OS by following these steps:
- Enable Accessiblity Features with <Ctrl> + <Alt> + z
- Open a tab to chrome-extension://gjjabgpgjpampikjhjpfhneeoapjbjaf/_generated_background_page.html
- Open Developer Tools with <Ctrl> + <Shift> + j
- Enjoy!

Know more about Accessiblity at
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