Today, Microsoft announced the availability of Windows 10 Insider Preview build 16188 to the Fast ring. This new build includes a ton of new features related to PDF compatibility in Microsoft Edge.

Kudos to Microsoft for releasing this build earlier in the day than usual in order to ensure that I was flying at the time.

The new PDF features are a bit overwhelming and include:

PDF form fill capabilities. Now you can fill in PDF-based forms using Microsoft Edge, and then save and print them.

PDF annotation. The annotation capability in Microsoft Edge has been extended to PDF files in this build. Yes, you can use “Make a Web Note” to annotate PDFs too.

Table of Contents support. As with E-PUB files and e-books, you can now navigate through the structure of a PDF file using a Table of Contents pane. Just select an item in the TOC to jump to that part of the document.

Improved viewing and navigation. Now you can rotate PDF documents for better readability, use a new Layout menu to switch from one page to two-page layouts, and toggle page-wise scrolling for a better navigation experience in longer documents.

Additionally, Microsoft has added a few more features:

Windows Defender Application Guard. The firm has brought its Windows Defender Application Guard technologies to Edge in this build. Announced last September, this feature is only available in Windows Insider Previews for Enterprise users in the Fast Ring. It provides enterprises better protection from malware and zero-day attacks, Microsoft says.

Settings improvements. The Settings app has a new top-level Cortana item for all Cortana settings. And the Windows Insider Program entry in Update & Security now features a cute Ninja Cat icon.

Magnifier settings improvements. Magnifier settings have been “reimagined” with a better experience for those with low vision and for more casual users.

Update experience improvements. Based on feedback, Microsoft has replaced the modal Windows Update dialog from the past with a new interactive toast notification that will not interrupt your work.

There are a number of other smaller changes, improvements, and fixes, plus some known issues. Check out Dona’s blog post for more information.