How can I get window in an .mdx file?

• ✅ Test.svelte persists a Svelte store to local storage using the window object.
• ✅ I can import & use Test.svelte in /src/pages/good-to-go.astro with the client:only directive, as per the docs:

  import Test from "../components/Test.svelte";

  <Test client:only />

• ✅ But when I run the same code in /src/pages/no-go.mdx, I get the "Window is not defined" error:

• ✅ (Svelte components that don't depend on window run as expected in a .mdx file.)

How can I get window in the .mdx file?