NEXTJS_MISSING_OPTIMIZE_PACKAGE_IMPORTS

is a feature added in Next 13.5 that improves compilation speed when importing packages that use barrel exports and export many named exports. This replaces the configuration option as it optimizes many of the most popular open source libraries automatically.

Barrel files make the process of exporting code from a package convenient by allowing all the code to be exported from a single file. This makes it easier to import any part of the package into your application. However, since they export a lot of code from the same file, importing these packages can cause tools to do additional work analyzing files that are unused in the application.

For further reading, see:

• How we optimized package imports in Next.js

To fix this, you can add a config to for the package that uses barrel files. For example: