This line produces a deprecation warning: https://github.com/salesforce/lwc-test/blob/99d452cc25728ede816cdbd91614772cff4881a2/packages/%40lwc/jest-transformer/package.json#L33 See also: https://www.npmjs.com/package/@babel/plugin-proposal-dynamic-import?activeTab=code It should be replaced with `@babel/plugin-transform-dynamic-import`