JS:redirector-BWW

Hey everybody.

Most of the time when I open up Mozilla Firefox, Avast always alerts me with something called JS:redirector-bww[Adw]
Nothing particularly bad happens, But it’s really getting on my nerves when it always comes up when I open Mozilla.
I’ve attempted to try and remove it, but Avast does not detect it when I scan for it. Can someone please help me! It’s really annoying and I want to remove it!

Thanks.
I’m using Windows XP.

Follow instructions here https://forum.avast.com/index.php?topic=53253.0
when requested logs are attached, help will arrive