I've been using the 2020 pretest for a while and decided I could uninstall the 2019 version. Using the 2019 tlmgr, tlmgr remove --all didn't remove all. Then rm -rf texlive/2019 removed too much, leaving me with a broken system. I'm now re-installing. So what is the correct way to unistall neither not enough nor too much of 2019? Bob T.