I initially gave this extension 5 stars because it seemed useful during my first tests. After using it for a longer time, I found an important reliability problem.
Sometimes the extension plays the completion sound before the ChatGPT response has actually finished. For my workflow, this makes the notification difficult to trust, because hearing the sound no longer means the response is really complete.
I often run several long ChatGPT conversations in parallel, so accuracy matters more to me than simply having a sound notification. A false completion alert is especially disruptive because it makes me switch tabs too early.
I am updating my original rating because I do not want the previous 5-star review to mislead users who also depend on accurate completion notifications.
The extension may still be useful for some users, but in my case the premature completion alerts were a significant problem.