Hi. I found that upgrading 2019.3.7 to Unity 2020.1.0b4 makes infinite import loop. After a while editor showup, but I can't access any FBX and prefab asset. It shows rotating "loading indicator" on its icon and I can't click it on Project view. Console log shows infinite import loop found. But even it contains not only json file on Mathematics package. Upgrading to 2020.1.0b1~2 doesn't make this issue.