Source maps are indeed very helpful when they work, but in my experience, often they don’t for third-party modules. This seems to be an ecosystem thing. The doc

Source maps are indeed very helpful when they work, but in my experience, often they don’t for third-party modules. This seems to be an ecosystem thing. The documentation for package.json doesn’t mention sourcemaps? According to this bug [1], even the typescript compiler’s npm doesn’t include source or sourcemaps. [1] https://github.com/microsoft/TypeScript/issues/32207 https://github.com/microsoft/TypeScript/issues/32207