I was experimenting with Svelte these days and, on trying to integrate it with Axios, I was confronted with the following error:
Uncaught TypeError: can't convert undefined to object mergeConfig mergeConfig.js:92 create axios.js:27 app http.js:3 <anonymous> bundle.js:3922
Apparently there is not much information on the subject so, I asked on the Discord Channel and was promptly answered with this link: https://stackoverflow.com/questions/69420370/async-axios-call-not-executed-in-svelte-trying-to-use-the-result-raises-a-typee
TL;DR
Downgrade Axios to version 0.21.1 to solve the issue.