Ho to inject variable to IONIC_HTML_TO_SERVE using html-webpack-plugin

[prakasa-tkpd]

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Short description of the problem:

Its not problem, just additional step to using condition in file IONIC_HTML_TO_SERVE. How to parsing variable to IONIC_HTML_TO_SERVE using html plugin ?

What behavior are you expecting?

I can print webpack variable there.

Steps to reproduce:

1. Add config.ionic_webpack
2. Add html-webpack-plugin
3. Add Option variable
4. Print, but not show the option

insert any relevant code between the above and below backticks
new HtmlWebpackPlugin({
      filename: 'index.html',
      template: pathResolver('./src/index.html'),
      NODE_ENV: 'production',
    }),

Which @ionic/app-scripts version are you using?
3.2.3

Other information: (e.g. stacktraces, related issues, suggestions how to fix, stackoverflow links, forum links, etc)
Not yet other information.