OpenType 1.9.1 Beta review

After (very unfortunately) being delayed by over a year, the next version of the OpenType Spec, OpenType 1.9.1, has progressed from Alpha to Beta. 

OpenType 1.9.1 Beta Review - Typography | Microsoft Learn

The Beta review period is planned to be fairly short (shouldn't be a concern since most of the content has been available as alpha for a long time) before the new version is finalized and released.

For those interested to see in detail what has changed, there are "delta" pages that include change tracking. Note, though, that some chapters have had a lot of editorial revision, so on some pages it may be hard to "see the trees for the forest".

The most significant technical change is a change in the interpretation of COLRv1 sweep gradient data. This was originally intended to be the main focus for v1.9.1, until (i) events led to a delay and then (ii) it became a priority to get changes from OT 1.8.4 and OT 1.9 incorporated into the new edition of the ISO OFF standard that was underway.

The next most significant change is a complete, editorial re-write of the CFF2 and CFF2 CharString specs—now combined into a single chapter.

See the change log (or the "delta" pages) for more information on changes. The Beta Review landing page also provides links to issue reports that were address in this update.