The Matchers interface in @types/testing-library__jest-dom currently extends Record<string, any> interface (via TestingLibraryMatchers interface): https://github.com/DefinitelyTyped/DefinitelyTyped/blob/master/types/testing-library__jest-dom/matchers.d.ts#L1

This makes the Matchers interface unsafe. Because of Record, any unknown property or function is automatically any.

So, if I make a typo like expect('a value').toBee() (instead of toBe()) or use a non-existent matcher expect('a value').toBeXYZ(), TypeScript can't point it out, and I learn about the problem only in runtime when running the test.

There seems not to be any good reason for extending from Record; it should be removed from the type.