hey @novice -
this is what I see in your site with the developer pane open:
It should be possible to link a script in as you are trying to do and deploy with drag and drop.
I’m not sure, but it might be specific to this particular JS file - the error seems to suggest that there is a content policy in place, which sort of explains why it works locally but not on live? It’s a little confusing. I would probably research that error message and see if you can figure out what it means, exactly.
Have you tried loading in a different JS file?
What are you using the Mathjax for? is there a simpler way?