This add-on adds an icon to the tab of any page making a noise. It can't detect if a plugin such as Flash is making a noise, so a different icon is added to tabs running Flash. These are the icons:
|The tab is making a noise.|
|The tab has been muted. You can mute a tab by clicking on the icon.|
|The tab has active plugins.|
Released versions can be downloaded from https://addons.mozilla.org/firefox/addon/noise-control/
Want to add some functionality to Noise Control? Feel free to send me a pull request.
To get this repo in your Firefox profile, clone it and use the Add-on SDK tools to create a working version.
Add-ons are available for free, but developing and supporting them does take a considerable amount of time. Please consider making a donation to help me pay my bills. You can contribute any amount you like through PayPal via addons.mozilla.org. (Note though that for amounts smaller than about US$1, PayPal takes most of it.) If you prefer Bitcoin, my address is listed on the same page.