Running webpack with PrerenderSpaPlugin does not find or process the HTML or JS from output folder.

[claudionunezjr]

Issue Description

I've been trying to get this plugin working for several days now, but to no avail. What I've noticed is that my compiled JS isn't getting processed, which also means the generated HTML isn't either.

I'm compiling TS to JS along with the following plugins:

    plugins: [
        new CleanWebpackPlugin(),
        new HtmlWebpackPlugin({
            meta: {
                // Will generate: <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
                viewport: 'width=device-width, initial-scale=1'
            },
            title: 'nectar'
        }),
        new PrerenderSPAPlugin({
            indexPath: path.join(__dirname, 'dist', 'index.html'),
            outputDir: path.join(__dirname, 'ssg'),
            postProcess(renderedRoute) {
                // `postProcess` never gets called.
                console.log('html', renderedRoute.html);
                return renderedRoute;
            },
            renderer: new Renderer({
                renderAfterDocumentEvent: 'render-event'
            }),
            // Required - Routes to render.
            routes: ['/'],
            // Required - The path to the webpack-outputted app to prerender.
            staticDir: path.join(__dirname, 'dist')
        })
    ]

If I set the Puppeteer Renderer option renderAfterElementExists instead of renderAfterDocumentEvent, I will get the [prerender-spa-plugin] Unable to prerender all routes! output in the terminal.

Environment

OS: MacOS Catalina
IDE: VS Code
Node Version: v12.6.0
Webpack Version: 5.12.3
Webpack CLI: 4.3.1
Prerenderer Spa Plugin: 3.4.0
Framework: Nectar (basically vanilla JS - nothing magical)

Reproduce & Full Project Code/Setup

Project code: https://github.com/claudionunezjr/nectar
Clone: git clone https://github.com/claudionunezjr/nectar.git
Install the packages: npm i
Run the project: npm run prod

Result/Output:

$ npm run prod

> nectar@1.0.0 prod
> export NODE_ENV=production && webpack --progress

is prod true
98% emitting after emit PrerenderSPAPlugin

...and hangs because the JS code which calls the document event isn't processed.