I great extension to have if you download files using a slower internet connection. I prefer to download files one at a time because of the slow connection, so the alert is nice to have some I can download the next ASAP.

v1.2 worked fine for me, but since upgrading to v1.4 (skipped v1.3), I can't choose the voice I want. It uses the same voice, regardless of what I have selected in the dropdown menu. Selecting the completion tone works as expected. Using FF62dev + OSX 10.10.5.

Update 1: I discovered that this is a problem only with the "en-US" voices... all en-US voicee use the default male voice (Alex), but when I choose another nationality, like Tessa (en-ZA), it does change the voice.

Update 2: Both the github and download sound addon have 64 voices on the drop down menu.