how to get window.{some_variable} from current active tab, in chrome extension

So,i am injecting a convert.js file into the current active tab.
inside the convert.js file, i have to fetch some window.{some_var}, which i have set when the page will load on the browser, i append those windows var, from server side rendering.

how to acces those window.{some_variable{ from my convert.js file.



based on a condition, the convert.js file injected into current tab.

I tried with sendMessage and listener, but giving me undefined.

but if the do window.{some_var} in browser console, its printing properly.

need help….