How to debug a Payload-based app including Payload Core functions with source code?

[MurzNN]

Sometimes we need to debug not only our custom app, built on Payload CMS, itself separately, but including the Payload CMS sources, so from our custom function, step into the Payload Core function to check how the data is handled there.

But if we have Payload CMS installed using the NPM package, there are only TypeScript definitions and compiled sources available, which is not enough for debugging.

We can clone the Payload CMS git repository and link it into our custom project using pnpm link ../payload/packages/payload, and build the dist files using pnpm build:payload. But this build will again build the dist files without source maps, and we will get the same result.

So, could anyone suggest the easiest way to achieve debugging Payload Core functions from a custom project app?

P.S. Sorry if this question is dumb for advanced developers and not related directly to Payload, but more like a general TS-based development question, but still, I believe that the answer should be very helpful for many other Payload users.