Webpack 5 with DLLPlugin does create empty analysis (contents of chunks are not visible)

Issue description

When using webpack 5 with a vendor webpack config that uses DLLPlugin, the webpack report created for this bundle does not display any contents within the chunks.

The following example uses the same code & webpack config, the only difference is the webpack version.

Webpack 4 (v4.44.2) Output:

Webpack 5 (v5.9.0) Output:

Technical info

Sample repository to reproduce this error can be found here (it's basically a copy of webpacks own dll example with installed webpack-bundle-analyzer):

1. npm i in both webpack4, webpack5 directories
2. npx webpack in both dll directories
3. Analyzer output will be in dist (versions are also checked in)

Debug info

See above.

Use the linked webpack5-analyzer-dll-demo reproduction, install dependencies in both webpack4 and webpack5 directories, and run npx webpack in each dll directory. Compare the analyzer output in dist, focusing on why the webpack 5 report shows empty chunks while webpack 4 displays their contents; done means webpack 5 chunk contents are visible.