how do I clear open tabs?

Hi, I think you mean on Android. The problem is that the notifications appear on the device lock screen, or on the device notification bar, or on the Firefox new tab/home page? (Mine don't appear inside Firefox, but our settings might be different.) For the device notification bar, I think you can just swipe them away like other app notifications, but if yours are stubborn, hmm, what kind of issue do they refer to?