Why doesn't Webpack emit chunks when using webpackMode: "weak"?

I'm transitioning a legacy app to Webpack. I'm using Webpack 5.56 (latest at time of writing).

My app is localised and I have a folder with a handful of locale files,

locales
  - locale.en.ts
  - locale.de.ts
  - etc

Each of these locale files is an ES module and they all export (different implementations of) the same functions — getText, printNumber, etc. I have a wrapper module which dynamically imports the correct locale for the current user:

// localization.ts

interface LocaleModule {
    getText(text: string): string;
    // etc
}

let module: LocaleModule;
import(`locales/locale.${currentUser.language}`).then(m => {
    module = m;
});

export function getText(text: string): string {
    return module.getText(text);
}

I know the current user's language when the page is being rendered. I want to include the correct locale.*.js script as an initial chunk, so that:

• The browser doesn't have to wait for the main chunk to load before it can start downloading the locale file.
• The functions in localization.ts can be synchronous.

This seemed like it'd be a good fit for webpackMode: "weak", since I'd like to get an error in the console if the locale file is missing for whatever reason (rather than silently degrade performance). The docs seem to explicitly call out my use case:

This is useful for universal rendering when required chunks are always manually served in initial requests (embedded within the page).

Here's my code:

let module: LocaleModule;
import(
    /* webpackMode: "weak" */
    /* webpackChunkName: "locales/[request]" */
    `./locales/locale.${currentUser.language}`
).then(m => {
    module = m;
});

However, it seems webpackMode: "weak" causes Webpack to emit no chunks for the referenced modules at all. There aren't any locale files in Webpack's output folder. I can’t very well include a chunk in the HTML if it was never emitted!

What's the reason for this behaviour? Is there a clean way to get Webpack to emit chunks for dynamically imported modules but not download them asynchronously? (I know that I could use webpackMode: "lazy" and just include the chunk upfront in a script tag, but I'd like to get an error if the locale file is missing.) Or do I have an XY problem, and there’s some better way to do this which I’m unaware of?

from Why doesn't Webpack emit chunks when using webpackMode: "weak"?