How to turn on Facebook's dark mode on any device

You can enable Facebook dark mode on your iPhone, Android, or desktop web browser with a few clicks or taps.
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Easily Enable Kindle Dark Mode and Improve Your Reading Experience

On a Fire tablet, open a book and tap the page, then tap Font (Aa) > Layout > Black. This article explains how to use Dark Mode on Kindle. The information applies to certain Kindle models made in 2017 ...