RangeError: Maximum call stack size exceeded

[BillyCallahan]

I'm trying to integrate a vanilla js/css theme with sapper. To ease the process I grabbed the bundled version of my theme (bundled with webpack), and I just copied it where I needed it. But I keep getting the same error while compiling, wether I'm using rollup or svelte-loader:

✗ client
src/routes/index.svelte
Module build failed (from ./node_modules/svelte-loader/index.js):
Error: RangeError: RangeError: Maximum call stack size exceeded

Do you think I should try to merge the webpack configs instead of importing the bundle ?

[Conduitry]

This sounds like a duplicate of #4694. If you think this is a separate bug, please provide a specific reproduction. If this is a support question, please ask in the Discord chat or on StackOverflow, but both of those places will also first want a particular reproduction to look at.

[BillyCallahan]

My bad, I couldn't find this issue.
This is exactly the same problem I encounter.
Thank you