how do i unsubscribe to a thread?

hi, i have just looked at the thread about Opera and there's an envelope icon next to it, if i hover there, it says i'm subscribed to the thread. it's a mistake. how do i unsubcribe to a thread? thanks

 

thanks Ron, i'll see if i can work it out. i hope it's easier than working out cookies

 

i got abit worried for a second, but i think i did it. thanks again, Ron

 

i agree.