What is the ruling on discussing worldly matters while waiting for the burial of the deceased?

The Shaykh : This is also something that should not be done. You will find that some people, when they are waiting for the funeral to be buried, gather in groups and engage in casual conversation, to the point where you may hear some of them laughing heartily and the like. This is a mistake; this is not a place for such behavior. For this reason, they said that the person accompanying the funeral should be dignified and should be reflecting on his own end, knowing that he is now waiting for this deceased person to be buried, and tomorrow people will be waiting for his burial. Just as he buried others, he will be buried, as Ka'b ibn Zuhayr said:
"Every son of a woman, no matter how long his safety lasts, *** will one day be carried on a wobbly vehicle" We ask Allah to make our endings and yours good.