Cannot load the application if the browser doesn't have slash at the end of the URL

[nemonemi]

Prerequisites

• I confirm my issue is not in the opened issues
• I confirm the Frequently Asked Questions didn't contain the answer to my issue

Environment check

• I'm using the latest msw version
• I'm using Node.js version 18 or higher

Browsers

Chromium (Chrome, Brave, etc.)

Reproduction repository

No repo

Reproduction steps

...

Current behavior

My application has a base path configured in the Vite config and the React router.

I've configured MSW to be loaded from the relative path.

export async function enableMocking() {
  const worker = setupWorker(...handlers);

  return await worker.start({
    serviceWorker: {
      url: 'mockServiceWorker.js',
    },
    onUnhandledRequest: 'bypass',
  });
}

The file gets loaded

But the screen doesn't, and it throws this in the console:

Error: [MSW] Failed to locate the Service Worker registration.

This most likely means that the worker script URL "mockServiceWorker.js" cannot resolve against the actual public hostname (localhost:4200). This may happen if your application runs behind a proxy, or has a dynamic hostname.

Please consider using a custom "serviceWorker.url" option to point to the actual worker script location, or a custom "findWorker" option to resolve the Service Worker registration manually. More details:  at startWorkerInstance ... etc.
  | startWorkerInstance | @ | msw_browser.js?v=3c07e0f6:1097
-- | -- | -- | --
  | Promise.then (async) |   |  
  | (anonymous) | @ | main.tsx:37
  | Show less

</span></div>

However, if I would to add the / at the end of the URL, then everything works as expected.

If I set the base path in the MSW config, then I get an infinite screen reload for the URL without the \, but works for the URLs with it.

worker.start({
    serviceWorker: {
      url: '/supplier-management/lifecycle/approved-suppliers/mockServiceWorker.js',
    },
    onUnhandledRequest: 'bypass',
  });

Why would the loading of the resource depend on the slash in the URL?

Expected behavior

The URL without the slash at the end should load normally with mockServiceWorker properly setup.