UserAgent: Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/69.0.3497.100 Safari/537.36

Steps to reproduce the problem:
1. Make sure you've configured Chrome to support English and French languages.  Settings --> Languages --> Add languages --> French (france)
2. View and interact with this JSFiddle in the latest version of Chrome:  https://jsfiddle.net/orcd2914/8/
3. Change the speechSynthesis playback speed to 500%.
4. Click on the "Read It to Me" button.  It works!
5. Change the language to French (still using 500% playback speed).
6. Click on the "Read It to Me" button.  Nothing happens.
7. Change the playback speed back to 100%.
8. Click on the "Read It to Me" button.  Nothing happens.
9. Nothing continues to happen until you click on the "Stop" button, and set the speed back around 25%-200% for the French language, and then click on the "Read It to Me" button where it works.

What is the expected behavior?
It appears that the French language speechSynthesis rate cannot be set higher than 2.  If you do set it higher, nothing happens when window.speechSynthesis.speak(speech); is called.  If the language doesn't support that rate, it should throw an error to the onerror event that I bound in the fiddle, but it currently does NOT.

Also, it appears that window.speechSynthesis.cancel(); has to be called if the rate was set too high before any speechSynthesis.speak call will work again, no matter the configuration.  If the speech synthesis fails, it should work again once I've changed the configuration without having to call window.speechSynthesis.cancel();

What went wrong?
SpeechSynthesis sometimes doesn't work with the provided rate.  When it fails, it is not firing an onerror event, and nothing works again until you call window.speechSynthesis.cancel();

Did this work before? N/A 

Does this work in other browsers? N/A

Chrome version: 69.0.3497.100  Channel: stable
OS Version: 6.1 (Windows 7, Windows Server 2008 R2)
Flash Version: 

I've also seen this happen when the French language playback speed is set low (25% - 50%).  It can be reading the text mid-sentence and just stop working all of a sudden (doesn't even finish reading the whole text - it just stops and fails).