We currently treat app extensions like separate apps, which means there are a lot of duplication.

This will be fixed by:

• Deduplication of runtime native libraries (libmono, libxamarin). This requires having these as frameworks, putting them in the main app only and having a rpath=../../Frameworks in the extension's native executable.
  • Blocked for libmono because we don't have libmono as a framework yet (Mono: the runtime packages for .NET 6+ do not contain the runtime as a .framework for iOS/tvOS/watchOS runtime#42846). We can still do this for libxamarin though.
• Deduplication of AOT-ed assemblies. This requires building assemblies to frameworks.
• Deduplication of linked output. This requires running the linker only once for all extensions + the main app, with all the assemblies in one big closure.
• Deduplicate user frameworks between the app extensions and the app (tracked here: Put user frameworks in the container app bundle for app extensions #17876).
• Deduplicate icudt.dat between app extensions and the app (tracked here: Use the app container's icudt.dat file in app extensions #17877)