YouTube Dark Theme od Joe Ertaba

"Dark Theme for YouTube" extension converts YouTube theme to a highly customizable dark charcoal/blue theme. This extension is built on top of the default YouTube theme (native dark theme) so it is very light-weighted compare to using themes injected by Stylish or Stylus extensions.

Extension Preview:
https://www.youtube.com/watch?v=3lan4mQKxBk

Features:
Turn on and off from the action button to switch between light and dark themes
Accepts scheduling to turn on only on the specified period
Customize default color scheme
Inject custom CSS to alter the default theme (change font-size or font-family for instance)

How does this extension work?
This extension alters a cookie globally to turn the dark theme on and off. It also injects a lite script to the YouTube pages to alter the color scheme of the root element. In oppose to the other similar extensions, there is no resetting of the default theme or inverting the white theme with an inversion filter. Both of these methods are computationally inefficient. Instead, this extension asks YouTube to turn the native dark theme and only alter the global CSS variables to alter the colors.
Note that this method only works if the product supports native coloring. Some Google products do not yet support this feature.

Privacy Policy:
This extension does not send or receive any data to any server whatsoever.

Bug Report:
Please either use the commenting section of the FAQs page or the GitHub page for bug reporting.

Change Log:
0.2.0
Use the built-in dark theme (Material Design only)