how to resolve Uncaught SyntaxError: export declarations may only appear at top level of a module?

I'm making a browser extension and need to export a variable. However, whenever i run the code i get this

Uncaught SyntaxError: export declarations may only appear at top level of a module

This is my code:

// checkStatus.js
if (!localStorage.getItem("enabled")) localStorage.setItem("status", false);

let isEnabled = localStorage.getItem("enabled")

if (localStorage.getItem("enabled")) isEnabled = true;
else isEnabled = false;

export default isEnabled;

What am i doing wrong here?

Edit: it's a browser extension. unless i'm really stupid i can't add type="module" because there's no HTML