addResourceBundle after init and cacheing

Question

I am fetching namespaces for each component from a database that store JSON and adding them via addResourceBundle after init:

// Component
      i18next.addResourceBundle('ar', 'topicNS', {
        topics,
      });

I would like to add these to the cache/localstorage. I am using the localStorageBackend to cache the static JSON resources, how can I add to the cached namespaces after init?

I have tried using the resourcesToBackend plugin, but am not sure how to make it work.

// i18n.js
    backend: {
      backends: [
        LocalStorageBackend,
        HttpApi,
        resourcesToBackend((language, namespace, callback) => {
          // ???????
        }),
      ],
      loadPath: `${process.env.PUBLIC_URL}/locales/{{lng}}/{{ns}}.json`,
    },