mTLS from axios javascript request from the browser

I am currently struggling to make a mtls client validation from javascript code using axios. I created a client certificate, registered the host and added the WAF rule correctly. I can check it working with CURL requests. I am passing the .crt, .key and the same cacert.pem file that CURL uses as certificate authority. Nevertheless all my requests from axios in the browser get blocked by the WAF.
My request https agent looks more or less like: