SourceMap on LiveReload

I’m wondering why getting ionic runtime errors without relate to the source code (source map).
But I get a message about an uncaught (in promise) rejection to the built main.js file and not to the source code from the source map. Why not? In tsconfig.json the sourcemap option is true.

Running the app with the command:
ionic cordova run android -lc

Maybe this will help: Enable source-map for debugging via chrome inspector