Why do we have the pope?
Is it acceptable to laugh, clap, talk about non-faith related things, etc. during Mass? No, this is disrespectful and is contempt of the Sacrifice. The Mass revolves around the Sacrfice of the Holy Sacrament of Communion. And if the Sacrament is a perpetuation of the actual Sacrifice of Christ Jesus, then it is not at all acceptable. Imagine someone laughing and making jokes during the Crucifixion of the Lord Jesus. That is completely unacceptable, just how this kind of behavior during the Mass is unacceptable as well. Not all blame is on the laymen, but on the priests and the deacons as well. A cleric may talk about a sports game or something not in any way related to the Sacrifice of the Lord Jesus. This is an outrage and should never be done. How about being dressed inappropriately? This inculdes clothing and lack of clothing that is contemptiously undermining the solemnitiy of the most Holy Sacrfice. This would include sports team clothing, because the clothing is about the outside non-faith world rather than deep solemnity of the Sacrfice. This includes revealing and sexually inappropriate clothing, because revealing and sexually inappropriate clothing is inappropriate anytime, not just during mass, it is completely unnaceptable. This kind of clothing causes sexual concupiscence and is utterly abhorrant to the Lord. Imagine someone dressed inappropriately during the Crufixion of God! What an abomination!
"In like manner women also in decent apparel: adorning themselves with modesty and sobriety, not with plaited hair, or gold, or pearls, or costly attire [I Tim. ii. 9]"