According to a blog by Google, the new feature comes in to effect when the mobile network's effective connection type is "2G" or 'slow-2G, ' or when Chrome for Android estimates that the page load will take more than five seconds to load at the current network conditions and device capabilities. Google confirmed the announcement in a blog post and says they are extending the performance improvements offered by Chrome Lite page to HTTPS pages and will provide direct feedback to the developers who want it.
Of course, there are already a number of dark themes which you can download through the Chrome store, but the latest update means you won't need to shop around for a theme you like - you can just use the official one.
The feature is integrated with the dark mode in macOS Mojave so enabling dark mode at an OS level will switch Chrome to a dark theme as well. Because, essentially, Incognito and normal windows now look the same.
Summarily, settings to turn things off or on with regard to dark mode are not found in either the general settings menu or in under the above-mentioned "Developer options", for the time being.
In addition to the wider support for PIP mode, Chrome 73 will also let developers add hardware media key support to web apps. Chrome on Android will now show the "Lite" text in the URL bar for HTTP as well as HTTPS webpages to let users know when a webpage's optimised version is being displayed. Meanwhile, "Lite" pages are marked to the left of the Omnibar with a blue speedometer icon and text. Fortunately, Chrome 73 has no such issues; you can visit sites like Facebook, Twitter and others and each webpage will still appear in a complete dark mode.
However, the feature is not applicable to secure pages when accessed via Chrome's desktop version. Among the biggest new features of this release, we can mention support for Dark Mode on macOS.