tsconfig.json

{
	// https://www.typescriptlang.org/docs/handbook/compiler-options.html
	"compilerOptions": {
		// rules
		"forceConsistentCasingInFileNames": true,
		"noImplicitReturns": false,
		"noUnusedLocals": true,
		"strict": true,

		// decorators
		"experimentalDecorators": true,

		// output & paths
		"outDir": "./dist/",
		"module": "ESNext", // changed from commonjs to ESNext to ensure typescript outputs code that can be split by webpack (with commonjs, the dynamic imports were removed)
		"target": "ES2019",
		"removeComments": false, // to be sure comments required by webpack to split are still present
		"moduleResolution": "node", // https://vuejs.org/v2/guide/typescript.html
		"allowSyntheticDefaultImports": true,
		"esModuleInterop": true, // for lodash imports (https://github.com/lodash/lodash/issues/3192)
		"allowJs": true,
		"sourceMap": true,

		"declaration": true,
		// "declarationDir": "./dist/types", // declarationDir cannot be set if declaration is false

		"importHelpers": true,
		"lib": ["dom", "es2019.array"]
		// "typeRoots": []
	},
	"exclude": ["node_modules", "modules", "dist", "public", "webpack"]
}