To support PWAs the company has enabled different required technologies through EdgeHTML 17, including Service workers, push notifications, Fetch networking, Cache API, etc., in the latest Windows 10 Insider builds. The main events are some new graphics options and, for Windows 10 S users, a way to go completely password free.
Eye Control improvements: This feature introduced with the Fall Creators Update has been improved with easier controls for scrolling, quicker access to common tasks and the ability to pause (hiding the launchpad) when you need to.
Privacy: All companies collect user info on the pretext of further enhancing their service. By default, it uses full display brightness, so you'll want to change that if you're not plugged in.
Microsoft explained that it makes more sense for developers focusing on fully-tailored UWP experience to build things from the ground up using native technologies. Microsoft says a lot of modern machines are capable of playing HDR but need to be calibrated in the factory to be able to do so.
Graphics improvements: More PCs can support HDR video thanks to a new experimental calibration tool, available in Settings Apps Video playback.
Windows 10's Microsoft Store has always been criticized for its rather lacklustre selection of apps.
There are also new graphics settings for multi-GPU systems (Settings = System = Display = Advanced graphics settings). Today's Preview build brings one of the longest changelogs, with a number of features receiving fixes and improvements. The browser also gains the ability to print "certain types of webpages" in a clutter-free mode without ads and other unnecessary page elements.
If you don't want to go all Windows Insidery, you can already get most of these perks from desktop Chrome already, and Apple's WebKit engine which powers Safari is in the process of adding the necessary tech to support PWAs as well.