・[Window] → [Package Manager]
・[Advanced](ギアアイコン) → [Advanced Project Settings]
・[Enable Pre-release Packages]にレ点(チェック)を入れる。
・[Packages] → [Unity Registry]
・[Install]
・[Window] → [Package Manager]
・[Advanced](ギアアイコン) → [Advanced Project Settings]
・[Enable Pre-release Packages]にレ点(チェック)を入れる。
・[Packages] → [Unity Registry]
・[Install]