2026.9.1

• Updated Skia to m154.
• Updated qpdf to 12.4.1.
• Fixed an issue where garbage collection could corrupt PDF tag attributes during concurrent PDF generation (found and fixed by @Lurtz7 in #1483),
• Improved PDF/UA-1 compatibility when generating ZUGFeRD and Factur-X invoices.
• Fixed an issue in the DocumentOperation API where DocumentAttachmentRelationship.Supplement was incorrectly mapped to /Alternative.
• Improved handling of stream-writing exceptions during PDF generation.
• The ShowInCompanion API now automatically starts the Companion App if it is not already running (requires Companion App 2026.9.0 or newer).
• Improved exception messages related to Settings.ThrowOnMissingFontFamilies, Settings.ThrowOnMissingTextGlyphs, and Settings.UseSystemFonts.
• Reduced connection time to the Companion App on Windows.
• Added missing license files for dependencies.