Long story short: when I click the clone default arcgis pro python environment, it clones. And then when I click the dot next to the cloned environment to select it, then press ok, I get stuck with the loading bar (as per the attached image) for ages (30 mins + ) with no sign of the new environment being activated. If I restart Arc the cloned environment has not been activated. Am I doing something wrong, or is this just a bug? I've restarted my PC and the issue persists.