SourceMaps not working against minified content

[lancejpollard]

Not sure why the code is not getting sourcemapped to TypeScript (unminified), I see the //#sourceMappingURL=index.js.map in the dist/index.js file, is this fixable? See my error from https://github.com/webtoon/psd/issues/100:

my-app/node_modules/.pnpm/@[email protected]/node_modules/@webtoon/psd/dist/index.js:397
    throw new Le();
          ^
          
Le
    at wt (my-app/node_modules/.pnpm/@[email protected]/node_modules/@webtoon/psd/dist/index.js:397:11)
    at fn (my-app/node_modules/.pnpm/@[email protected]/node_modules/@webtoon/psd/dist/index.js:1188:76)
    at Rn (my-app/node_modules/.pnpm/@[email protected]/node_modules/@webtoon/psd/dist/index.js:1490:13)
    at Function.parse (my-app/node_modules/.pnpm/@[email protected]/node_modules/@webtoon/psd/dist/index.js:1982:15)
    at <anonymous> (my-app/tmp/psd.ts:162482:21)
    at Object.<anonymous> (my-app/tmp/psd.ts:162490:4)
    at Module._compile (node:internal/modules/cjs/loader:1376:14)
    at Object.F (my-app/node_modules/.pnpm/@[email protected]/node_modules/@esbuild-kit/cjs-loader/dist/index.js:1:941)
    at Module.load (node:internal/modules/cjs/loader:1207:32)
    at Module._load (node:internal/modules/cjs/loader:1023:12)

Node.js v20.10.0

I am using Next.js, do I need to do anything fancy do you think, to get your sourcemaps?