Release Notes

APDFL v21.0.0PlusP1d (September 4, 2026)

New Features:

• Brotli Compression Support — Added support for Brotli compression when saving PDF files through the new PDSaveAddBrotli flag. Brotli can help reduce PDF file sizes by providing more efficient compression for supported stream data, which can improve storage efficiency and reduce transfer times.
  This capability is based on a PDF Association extension to PDF 2.0 and is not part of the ISO 32000-2:2020 standard. PDF processors which do not support this extension may be unable to read Brotli-compressed streams.
• Tagged PDF Support in Web2PDF — Added tagged PDF support to Web2PDF for improved accessibility. Tagged PDFs include structure information that screen readers and other assistive technologies use to read a document in the correct order. This makes the PDFs Web2PDF generates accessible to users with disabilities and helps meet accessibility requirements.

Changes:

• The WebToPDF plugin is now included in the APDFL NuGet package (Windows x64/ARM, Linux x64/ARM, macOS ARM), with a new CreateDocFromWebPage sample.
• Corrected an issue flattening XFA documents where checkbox fields with non-zero margins could be slightly cropped when using Forms Extension.
• OCR data-only NuGet packages no longer pin specific target frameworks.
• With this release, the NuGet package version has been increased to 21.1.0.
• With this release, the Maven package version has been increased to 21.1.0.

Open Source Updates:

• Expat 2.8.3 (addresses CVE-2026-7522)
• giflib 6.1.3 (addresses CVE-2026-26740)

Problem Corrections:

• SF47594 – Corrects an issue during PDF/A conversion that could leave fonts unembedded when problematic fonts were encountered.
• SF47595 – Corrects a problem where converting to PDF/A Part 2 or later could leave Optional Content (layers) misconfigured.
• SF47641 – Corrects an issue where fonts using WinAnsiEncoding could be unnecessarily recreated during PDF/A conversion.
• SF47643 – Corrects a problem where re-subsetting Type 1 fonts could result in missing glyphs.
• SF47650 – Corrects a problem where applying a redaction to an image could unexpectedly affect the same image reused elsewhere.
• SF47659 – Corrects a problem when long paths are used on Windows for temporary files.
• SF47664 – Corrects a case where the Optimizer Report could indicate an incorrect previous image size.
• SF47680 – Corrects a color-conversion error when nested Form objects are present.
• SF47681 – Resolves a memory leak in PDSysFontAcquirePlatformData().
• SF47683 – Corrects a stack overflow that could occur parsing a crafted PDF with deeply nested Forms.
• SF47684 – Corrects a crash that could occur rendering a page with an invalid JBIG2 image.

APDFL v21.0.0PlusP1c (July 19, 2026)

New Features:

• Added support for OCR with Vietnamese text.
  Optical Character Recognition (OCR) now supports recognition of Vietnamese-language text, including Vietnamese-specific characters and diacritical marks. This enhancement improves text extraction accuracy and searchability for scanned documents containing Vietnamese content.

Changes:

• Forms Extension installers now support the Modern C++ interface.
• The XPS2PDF plugin now reports a specific error when the joboptions file cannot be found.
• Corrected installer documentation that still referenced APDFL 18.
• With this release, the Maven package version has been increased to 21.0.1.
• With this release, the NuGet package version has been increased to 21.0.1.

Open Source Updates:

• Boost 1.91.0
• cURL 8.21.0
• Expat 2.8.2 (addresses CVE-2026-45186)
• libTIFF 4.7.2
• OpenSSL 3.6.3

Problem Corrections:

• SF45180 – Improves flattening of XFA documents where a Button field has no Caption but a Text Label overlaid on top of it.
• SF47401 – Corrects an issue where content could be clipped unexpectedly when flattening an XFA document with Forms Extension.
• SF47460 – Corrects an issue where some XFA documents, when flattened AsIfPrinted, showed content that was meant to be excluded.
• SF47461 – Corrects an issue where a heavily crowded Text Field shared across pages of an XFA document could be slightly clipped when flattened with Forms Extension.
• SF47486 – Improves flattening of XFA documents where a Button field has no Caption but a Text Label overlaid on top of it.
• SF47555 – Corrects a problem where System Font selection could choose a similarly named but different style variant in some cases.
• SF47562 – Corrects an issue preserving the grouping symbol in a decimal value for a numericEdit field when flattening an XFA document.
• SF47581 – Corrects a problem where rendering a document with minor Page Content errors raised an error when it previously did not.
• SF47585 – Corrects a small memory leak that could occur when subsetting fonts.
• SF47591 – Corrects an issue where a PDF's Producer property still reported APDFL v18; it now correctly reports v21.
• SF47597 – This corrects a problem during Color Conversion where the inherited GraphicState would be changed unexpectedly in some cases.
• SF47599 – Corrects an issue where rendering to a CMYK-based space would not preserve K-only content as pure black.
• SF47603 – This corrects an issue with the Color Conversion option mPromoteGrayToCMYK when enabled, which would result in unexpected Gray values.
• SF47610 – This corrects a problem where Color Converting a Page could unexpectedly affect a shared Form on another page.

APDFL v21.0.0P1b (May 22, 2026)

Datalogics is pleased to announce the release of APDFL v21.0.0Plus1b. This release is a major upgrade built on the Adobe PDF Library (PDFL) v21.0 core libraries and includes a wide range of new features, performance improvements, compatibility enhancements, and problem corrections.

New Features:

• Modern C++ SDK — Built on the same APDFL runtime as the existing integration libraries, the Modern C++ SDK provides a C++17-based interface featuring RAII-based resource management, exception-driven error handling, move semantics, std::unique_ptr / std::shared_ptr ownership models, strongly typed flags, and a unified datalogics_interface namespace. These enhancements reduce boilerplate code, simplify resource management, and enable more natural integration of PDF functionality into modern C++ applications.
  The Modern C++ SDK requires a C++17 compiler and is supported on Windows (MSVC 19.3+ / Visual Studio 2022 v143 toolset, x64 and ARM64), Linux Rocky 9+ (Clang 18+ with libstdc++11, x86_64 and aarch64), and macOS 15+ (Apple Clang 16.4+ / Xcode 16+, x86_64 and arm64).
  The existing APDFL C++ interface will now be referred to as "Adobe C/C++" and remains fully supported. Existing integrations can continue unchanged, and migration to the Modern C++ SDK is optional.
• WebToPDF — A new Plug-In for APDFL that converts an HTML file tree on disk, or a URL, to PDF. Available on Windows 64, Windows ARM, Linux x64, and Linux arm64.
• Added support for the Chinese GB18030 font — Enables correct rendering and processing of Simplified and Traditional Chinese characters in documents that use GB18030-compliant fonts. This improves compatibility with Chinese-language PDFs and helps ensure accurate display of multilingual text content.
• New ListStructureTree Sample (Modern C++) — This sample walks the logical structure tree of a tagged PDF document and prints each element's struct type (/S), parent chain, and kid entries (child elements and marked-content references). Available for the Modern C++ interface.

Problem Corrections:

• SF44603 – Word Finder: Fixed incorrect positioning of Arabic diacritical marks (harakat) in extracted text. In certain PDFs, combining marks such as Damma (U+064F) could be attached to the wrong base character when the diacritic was spatially positioned between two Arabic glyphs with similar overlap.
• SF46074 – Resolved a problem with WordFinder processing Thai diacritics.
• SF46900 – Corrects an issue where updating Page Content could cause text contained within Marked Content to unexpectedly be located outside of the Marked Content.
• SF47417 – Corrects an issue where updating Page Content could cause text contained within Marked Content to unexpectedly be located outside of the Marked Content.
• SF47421 – Corrects a problem saving a DeviceN rendered image to a TIFF where the TIFFTAG_PHOTOSHOP tag data would be incorrect.
• SF47454 – Fixes a Stack Overflow that could occur setting Page Content during PDF/A conversion for Property Lists that are improperly defined.
• SF47481 – Rendering has been improved to be more resilient against problematic content that would previously raise an error. Some error strings that were meant to have a string format specifier used in combination with the non-fatal error argument were missing and have been added.
• SF47530 – Corrects a problem where converting a document to PDF/A could misinterpret the CTM for an ImageMask in some cases.