How to make resources on another site being cached by Cloudflare?

Hi,

I have a website a.com that is cached by Cloudflare.

In the page https://www.a.com/index.htm, it put two resources:

  1. https://www.a.com/a.jpg
  2. https://www.b.com/b.jpg

Based on my test, only a.jpg is cached by Cloudflare, b.jpg is not cached. Is there a way to make b.jpg be cached as well, without having added b.com to Cloudflare?

In a word: No.

In more words: move b.jpg to the domain that is using Cloudflare.