Why on earth is there a dancing jar of marmite taking up the bottom right sixth of the screen, and how do I get rid of it? I'm interested in what aging means h

Why on earth is there a dancing jar of marmite taking up the bottom right sixth of the screen, and how do I get rid of it? I'm interested in what aging means here. Presumably it is different to just 'having it in a jar in the cupboard' because then all jars are aged in the supermarket for a few weeks or more. Looks like I've got my afternoon wikipedia rabbit hole sorted.