Chrome Extension to include content script from the Web -

i'm trying include content script tabs loaded web (eg. https://www.somesite.com/somescript.js ). not library, rather (every week) changing script. change frequent not want users keep updating often. have looked @ content security policy , added domain there, has allowed me include background scripts web doesn't seem work content scripts.

ps. tried using js loaders (since needed multiple files , callback), inject script in isolated world of tab , not content script.