官方认为使用预览包有风险，在Unity2020之上的版本隐藏了不在活动开发中的软件包以及仅仅只作为其他包的依赖项的软件包。
隐藏的包可通过Add package from git URL来添加。输入包名，回车即可。
添加之后仍然不会出现在列表中，而是直接后台下载。待下载完成自动导入。
一下是所有被隐藏的包名：
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 |
com.ptc.vuforia.engine com.unity.2d.entities com.unity.ai.planner com.unity.aovrecorder com.unity.assetbundlebrowser com.unity.assetgraph com.unity.barracuda com.unity.barracuda.burst com.unity.build-report-inspector com.unity.cloud.userreporting com.unity.collections com.unity.connect.share com.unity.dots.editor com.unity.entities com.unity.film-tv.toolbox com.unity.google.resonance.audio com.unity.immediate-window com.unity.mathematics com.unity.meshsync com.unity.multiplayer-hlapi com.unity.package-manager-doctools com.unity.package-manager-ui com.unity.package-validation-suite com.unity.physics com.unity.platforms com.unity.platforms.android com.unity.platforms.linux com.unity.platforms.macos com.unity.platforms.web com.unity.platforms.windows com.unity.playablegraph-visualizer com.unity.render-pipelines.lightweight com.unity.rendering.hybrid com.unity.renderstreaming com.unity.scene-template com.unity.simulation.client com.unity.simulation.core com.unity.simulation.capture com.unity.simulation.games com.unity.standardevents com.unity.streaming-image-sequence com.unity.test-framework.performance com.unity.tiny.all com.unity.transport com.unity.upm.develop com.unity.vectorgraphics com.unity.webrtc com.unity.xr.googlevr.android com.unity.xr.googlevr.ios com.unity.xr.legacyinputhelpers com.unity.xr.oculus.android com.unity.xr.oculus.standalone com.unity.xr.openvr.standalone com.unity.xr.arsubsystems com.unity.xr.interactionsubsystems com.unity.xr.windowsmr.metro com.unity.nuget.newtonsoft-json |
