Is this a version of Firefox later than version 3.6? I can't see Firefox Signatunes on my 3.6 version.
It seems to be a Firefox Add-on, so you could check the add-ons in the Tools menu, to see if it is actually installed.
If not, try the Foxytunes web site and see if it will install from there;
http://www.foxytunes.com/signatunes/
Let me know if that helps.
Mark
Just today, I installed the latest version of FF, which was supposed to have Signatunes included. The Signatunes installs a treble clef icon at the bottom of Yahoo! emails you are sending, so the recipient may listen to what is playing on FoxyTunes at the time of the sending of the email.
I have used FoxyTunes for quite some time and love it - just want to share with my email recipients.
So, the update is done and... no icon. Any ideas out there.
Please keep replies simple - I'm not advanced in computers. Thanks.

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