The README that corresponds to this release is:
https://github.com/mozilla/policy-templates/blob/v1.17/README.md
This release provides support for the following new policies:
EncryptedMediaExtensions
PDFjs
Note: DisableBuiltinPDFViewer has not been deprecated. You can either continue to use it, or switch to using PDFjs->Enabled to disable the built-in PDF viewer. This new permission was added because we needed a place for PDFjs->EnabledPermissions.
This release updates the following policies:
Authentication - Added support for PrivateBrowsing