The following two software have been released. The updates include a fix for PDF bookmarks in addition to regular updates for PDFium (Chromium 96 compatible).
Issue of breaking hierarchical "outline" when merging PDFs
At the time of the July 2021 update, we migrated the iText used in CubePDF series from the previous version of iTextSharp to itext7. The update caused the hierarchical "outline" structure to be broken when merging PDFs (the root element was displayed at every page break) as shown in the figure below.
CubePDF Utility 1.6.1 and CubePDF Page 3.6.0 have improved this problem. However, even after the improvement, if you insert another PDF page between PDF files that contain hierarchical "outline" structure, the continuity of the outline will be broken on the corresponding page and the root element will be displayed again. We are currently considering this behavior, including how the outline information should be combined. If we make any fixes for this behavior, we will announce them in the release.
For CubePDF Utility and CubePDF Page users, please download the latest installer from CubePDF Utility download Page and CubePDF Page download Page respectively, and update by overwrite installation. The source code can be available from our repository on GitHub.