To enable Google Assistant voice search in Chrome, you need to update your browser to the latest stable version (v.87). Since the feature is behind the experimental flag, you need to visit the chrome://flags page to enable it. Below is the step-by-step instruction.
Steps to Use Google Assistant Voice Search in Chrome
You have now enabled Google Assistant voice search in your favorite browser Chrome. Google may replace the basic voice search in Chrome with Assistant in the coming days. So if you want to experiment with the feature before Google turn on it, enable it as given above. More Resources
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