Low disk space pop up, how do i set it to a different default size ?

Hi a few days ago my Kubuntu 23 popped up the message that I was running out of disk space, i had the option to change the value for the warning from its default to a different amount i increased it to 5GB. I then to action to delete some files so that I had more than 5GB disk space.

This pop up was very useful, I am about to setup another PC and I would like to also change the default to 5GB, but I cannot find where I should change this value from the default.

Any ideas where I may find this ?