Set the common headers in the nuxt.config.js for the axios module. Then make a request with the axios module.
It should merge the headers you add to the config with the default like the documentation says.
The headers are not changing.
I've created a example repo to recreate the bug.
https://jsonplaceholder.typicode.com/posts/1in the dev tools.
You should see that the common header set in
nuxt.config.js is missing from the request when it shouldn't be.