webpack-obfuscator is not generating sourcemaps

We use "webpack-obfuscator": "^3.5.1"
with
const webpackObfuscator = new WebpackObfuscator(
{
sourceMap: true,
});

but sourcemaps files not generating
I also opened stackoverflow question but without help.
[https://stackoverflow.com/questions/73569780/javascript-obfuscator-with-webpack-obfuscator-source-map-files-not-working](https://stackoverflow.com/questions/73569780/javascript-obfuscator-with-webpack-obfuscator-source-map-files-not-working)
Thank you in advance for any help :)

Start by reproducing the report with webpack-obfuscator ^3.5.1 and the shown sourceMap: true configuration, using the linked Stack Overflow context as background. Inspect the generated webpack assets and sourcemap output; done means the expected sourcemap files are generated or the issue is narrowed to a documented configuration limitation.

索引モデルが issue の本文から書いたものです。