Steps to reproduce:
When Dark Reader is installed and dark mode is on, it will glitch on some websites with embedded videos and images. Sometimes they partially load but have black bars, and sometimes you can hear the video but it just looks black. When dark mode is turned off, they display normally.
Videos and images should display normally regardless of whether dark mode is on, like in Chrome/Firefox/Safari
Orion and macOS:
Orion 0.99.108-beta, Big Sur & Monterey