u/Background-Pea-1773

Hi, I live on the first floor of a four floor apartment block in London. Been here about a year. In the living room there is this large crack - it hasn’t really changed since I moved in but someone said it was serious so thought I would ask here. It’s plaster on a brick wall and the crack is near identical on the other side of the wall. I don’t think it is expanding however. Any thoughts ? Is the building about to cave in?