https://docs.unity3d.com/ScriptReference/PlayerSettings.html
public static bool stripEngineCode;
Description
Remove unused Engine code from your build (IL2CPP-only).
If this is enabled, unused modules and classes of the Unity Engine codebase will be removed in IL2CPP builds. This will result in smaller binary size. It is recommended to use this setting, however, you may want to disable it if you suspect this causes issues with your project. Note that byte code stripping of managed assemblies is always enabled for the IL2CPP scripting backend.
Strip engine code在build setting的other setting中，勾选可以让代码进行压缩，自动不打包没有用到的代码，比如一个2DUI游戏没有用到Rigidbody等物理类的组件，但是勾选这个选项后可能会导致个别项目进行到有些地方直接崩溃，使用时还请慎重考虑