Is your feature request related to a problem? Please describe.
I find the current documentation incomplete for "Use webpack aliases to modify templates without changing the original files".
It indicates that you can customize the converse.js themes only by adding them as dependencies and configuring Webpack with the aliases.
Said previous steps are understood, however, it does not indicate what the next step would be to compile the project using that dependency library and generate the compile with the modified files.

Describe the solution you'd like
It should indicate in the documentation how to import the converse.js library into an index.js file in your new project, which must have the same file so that it can generate the compile overwriting the modified files to generate a custom theming.

I appreciate the collaboration that can help improve the documentation and allow to make custom themes neatly.