[O] Ask for feature: include other .org files from a (main) .org file

[Zihan, Sheldon Liu]

I want to place some customization codes in a separate file, and include it from other files later. For example, file config.org has a single line #+MATHJAX: align:"left" mathml:t. How do I include it in another .org file abc.org so that the net-effect is exactly same as I write that #+MATHJAX line directly in abc.org (#+INCLUDE doesn't meet this requirement)? Thanks.

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Regards,
Zihan, Sheldon Liu
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