I am very confused how to operate it. I went to this website that evidently has some ads or something last night and the avast never said anything. Now, when I go to same site, it gave me that fire engine warning and popped up saying that it found something but don’t worry it got rid of it. Said something about if I clicked on the abort button or whatever, it said something about cancelling the download. When I clicked on the button the warning started again.
Actually, avast’s detections in these cases are pretty accurate. I believe that you encountered this while browsing. It would be best to click Abort Connection on those circumstances. By the way, a false positive may be a reason too so if possible, please provide us the full alert details you may find in avast’s Logs for a better analysis.