Thank you for your reply. I'm now trying to use a Custom HTML particle instead. I've made sure that both "Process Twig" and "Process shortcodes" are ticked. However, I still can't get it to work. It seems that this problem is independent of safe_email. Even something simple such as [raw]
This is centered
[/raw] does not work inside the Custom HTML particle. On the other hand, when I enter the same shortcode in "Page Content" it does work.
Shortcode Core: 2.7.1
 What is slightly confusing though is that I see two tickboxes for Twig and shortcodes each, which can be ticked and unticked independently (see attached image).
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