That's correct! those features are not available on Confluence cloud.
From the Functional differences in Confluence Cloud page:
On Atlassian Cloud, Confluence uses a custom theme that can't be modified or updated using custom HTML or CSS. For more information on custom themes in Confluence Cloud, refer to Working with Themes
Have you further questions relate to this topic?
👋 Hello Community! My name is Stephanie Zhang, and I’m a product manager on the Confluence cloud team. Today, I’m excited to announce the rollout of Presenter Mode : a ...
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