How to secure the Safari web extension?

I'm tasked with securing a Safari browser extension that my organization created. (It was previously launched in other browsers, and still running on those. It is using WebExtensions.) I've searched for many hours on this and find very very little information on how to secure it. (Pretty much just https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/WebExtensions/Content_Security_Policy.) Is there anything more extensive/comprehensive?

By comparison, when looking for resources for securing the Firefox version of the extension, I found https://extensionworkshop.com/documentation/develop/build-a-secure-extension/, which I think is a great resource. Some of that content applies to Safari, but it's hard to know to what extent. I'll need to secure Safari web and Safari mobile (i.e. iOS), but for now I'm focused on web. (But if you have anything on mobile, then please let me know also.) Thank you!