itunes music playing without signing in

Hi, I just noticed today that I was able to play my Apple Playlists and I didn't sign in. When I asked Google why this happened I got this response: The "MultiSearch for Chrome" ext changed search to use search.searchsqout.com. I have no idea what that is and then It asked do I want to keep it or change it back. I hit change it back. However I don't see any change. The music still played. I use a MACBOOK PRO 2011 with MAC OS 13. I see a lot of other people have this problem. I could not ask a question on here until I signed in however. Can anyone help or explain why this is going on? Is this safe?