Kill the browser completely, reopen the browser and start text-to-speech with speechSynthesis.speak(string);
speechSynthesis.pause(); won't work till you refresh the page.
Same can be seen at, https://developer.microsoft.com/en-us/microsoft-edge/testdrive/demos/speechsynthesis/
This happens on both Mac and Windows, chrome 70.
Does anybody know a workaround?