Microsoft has issued Windows 10 Insider Preview Build 16215 to those on the Fast ring. And this a major release with tons of new features, including the addition of acrylic effects in the UI and the ability to pin Edge-based web apps to the taskbar.

Oh my.

Here’s what’s new.

Acrylic in the Start menu. If you have transparency enabled, you will now see acrylic effects—part of the Fluent Design System—in Start.

New-look Action Center. The quick actions area hasn’t (yet) been pulled out into a separate Control Center, but Action Center—which displays system and app notifications—has a new look that also includes acrylic effects. (Notification toasts also get an acrylic update this time around, too.)

Web app pins on the taskbar. Answering possibly my single biggest complaint about Microsoft Edge, Microsoft has finally added the ability to save web app shortcuts to the taskbar.

F11 full-screen mode in Edge. Microsoft Edge actually does support a true full-screen mode via a complicated keyboard shortcut, but in this build, Microsoft has finally done the right thing and made F11 a full-screen toggle, as with other browsers.

E-book annotations. Now you can annotate E-PUB-based e-books in Microsoft Edge with color highlighting, underlining, and comments capabilities.

PDF improvements. Microsoft Edge’s PDF reading capabilities are also improved with more highlight colors and Ask Cortana support.

Visual intelligence in Cortana reminders. Cortana will now automatically prompt you for a reminder if it sees an event poster in your camera roll. (This only works when you’re using a Microsoft account, have enabled the feature, and the device is plugged into a power source and on a non-metered network.)

Improved pen support in Cortana. Now, you can use your Surface Pen or another active pen (with press and hold support) with a new lasso tool to circle information on-screen and trigger Cortana. “Find a website with upcoming event info, or an event poster someone shared in social media,” Microsoftexplains. “Once you have the event on your screen, just press and hold the pen back button, circle the time information, and watch Cortana do her magic.”

Various handwriting panel improvements. The ink-based handwriting panel gets a number of updates in this release, including text shifting, text selection/editing, in-place and gesture-based corrections, and more.

Find My Pen. A new “where’s my pen” option in Find My Device will tell you where the last time you used your pen was.

Pen scrolling. You can now scroll more naturally with Surface Pen or other active pens, a big user request.

Easier emojis on a hardware keyboard. Now, you can trigger an emoji insertion panel with keyboard shortcuts: WINKEY + . (period) or WINKEY + ; (semicolon).

New Touch keyboard. Microsoft has created a new XAML-based touch keyboard for this release, though it’s not clear yet if it’s new, or based on a previous Microsoft soft keyboard like SwiftKey. It includes enhanced text prediction, an improved emoji experience, a one-handed mode, and shape writing. You can also dictate (English or Chinese) with your voice and microphone!

Improved Share experience. The new Share experience is already improving with a new Copy Link option so you can copy information to the clipboard.

Improved local media detection. UWP apps like Photos, Groove Music, and Movies & TV now do a better job of finding compatible media on your device.

My People improvements. The new My People experience has been improved in this build in various small ways.

HDR and advanced color settings. A new HDR and advanced color settings option in Display settings will help users take more control of HDR-compatible displays.

There are actually a ton of other new features in this build too, the list just goes on and on. Be sure to check out the Microsoft blog post for a complete rundown. I can’t remember a Windows 10 build with this many new features, ever.