Chrome extension failed to load javascript due to url related to protocol

I am developing a Chrome extension where I load a javascript file from an external domain that I don't have access to. This javascript in it loads other javascript with a relative protocol method //exemple.com/javascript.js

. And the problem is I am getting the error

Failed to load resource: net :: ERR_FAILED chrome-extension: //exemple.com/javascript.js

PS My manifest looks like this "content_security_policy": "script-src 'self' https://example.com 'unsafe-eval'; object-src 'self' https://example.com"