Seems there's a bug in the Action Centre, every time I have updates offered for Docker apps in it and go to apply them it downloads the new image, stops the container, and apparently omits deleting the existing container before trying to recreate it such that it fails with an error "A container with that name already exists", then the old container is restarted. Since afterwards the progress screen disappears to show the summary page that suggests nothing went wrong you'll only catch it if looki