External resources are no longer loaded by default (new LoadOptions controls) - Opening, previewing or saving a document no longer downloads the remote images, style sheets or linked files it references. New LoadOptions members let you allow specific hosts, inspect every request or restore the previous behavior.
Upgraded the underlying document engines.
Security - Updated System.Security.Cryptography.Pkcs to 8.0.2.
修复
Fixed FileTypeNotSupportedException when extracting annotations from EML documents.
Fixed documents annotated by older versions failing to open on .NET 8.
Fixed PDF page rotation by 90 degrees being lost on save.
GroupDocs.Annotation for .NET V26.6主版本2026年6月15日
功能
NuGet package has been split into per-target-framework runtime packages (adds .NET 6 and .NET 8).
Upgraded the underlying document engines.
Spreadsheet text-replacement font colour must now be set explicitly.
修复
Fixed image annotations failing on presentations (PPTX).
Fixed Visio (Diagram) area/redaction annotations rendering as empty outlines.
Fixed ArgumentOutOfRangeException when removing annotations from Visio documents with hyperlinks.
Fixed Diagram GetDocumentInfo returning no text lines.
Restore slide-preview generation for presentations.
Fixed System.NotImplementedException when annotating image files.
Fixed NullReferenceException when reading annotations from HTML documents with footnotes or endnotes.