It allowed me to turn the volume down, but when I tried to turn it back up, it didn't change. I could turn it down further and further all the way to off, but never could get sound back. Had to uninstall.

Nope, doesn't work per-tab or per-website. Just on a global basis, which is what I didn't want.

A extensão é fantástica, ela pega e aumenta o volume e vc pode escolher o quanto quer aumentar

This is excellent.Thank you!!!

First App that does the Job.

Thank you so much for this! Fixed the ear-bleeding issue with Facebook.

new: awesome thank you for the response!
old: i like the idea, but some logic fails. i've had it apply volume occasionally even when un-ticked.
it also fights with youtube, so when i use "enhancer for youtube" to change the volume, "persistent video volume" addon will take control which i dont really want.

This is really good! Support for controlling sounds in individual tabs would be even better, but as is is great too!