Pypdf

New Features (ENH)
- Simplify metadata input (Document Information Dictionary) (1851)
- Extend cmap compatibility to GBK_EUC_H/V (1812)

Bug Fixes (BUG)
- Prevent infinite loop when no character follows after a comment (1828)
- get_contents does not return ContentStream (1847)
- Accept XYZ destination with zoom missing (default to zoom=0.0) (1844)
- Cope with 1 Bit images (1815)

Robustness (ROB)
- Handle missing /Type entry in Page tree (1845)

Documentation (DOC)
- Expand file size explanations (1835)
- Add comparison with pdfplumber (1837)
- Clarify that PyPDF2 is dead (1827)
- Add Hunter King as Contributor for 1806

Maintenance (MAINT)
- Refactor internal Encryption class (1821)
- Add R parameter to generate_values (1820)
- Make encryption_key parameter of write_to_stream optional (1819)
- Prepare for adding AES encryption support (1818)

[Full Changelog](https://github.com/py-pdf/pypdf/compare/3.8.1...3.9.0)

Bug Fixes (BUG)
- Convert color space before saving (1802)

Documentation (DOC)
- PDF/A (1807)
- Use append instead of add_page
- Document core mechanics of pypdf (1783)

[Full Changelog](https://github.com/py-pdf/pypdf/compare/3.8.0...3.8.1)

New Features (ENH)
- Add transform method to Transformation class (1765)
- Cope with UC2 fonts in text_extraction (1785)

Robustness (ROB)
- Invalid startxref pointing 1 char before (1784)

Maintenance (MAINT)
- Mark code handling old parameters as deprecated (1798)

[Full Changelog](https://github.com/py-pdf/pypdf/compare/3.7.1...3.8.0)

Security (SEC)
- Warn about PDF encryption security (1755)

Robustness (ROB)
- Prevent loop in Cloning (1770)
- Capture UnicodeDecodeError at PdfReader.pdf_header (1768)

Documentation (DOC)
- Add .readthedocs.yaml and bump docs dependencies using `tox -e deps` (1750, 1752)

Developer Experience (DEV)
- Make make_changelog.py idempotent

Maintenance (MAINT)
- Move generation of file identifiers to a method (1760)

Testing (TST)
- Add xmp test (1775)

[Full Changelog](https://github.com/py-pdf/pypdf/compare/3.7.0...3.7.1)

Security (SEC)
- Use Python's secrets module instead of random module (1748)

New Features (ENH)
- Add AnnotationBuilder.highlight text markup annotation (1740)
- Add AnnotationBuilder.popup (1665)
- Add AnnotationBuilder.polyline annotation support (1726)
- Add clone_from parameter in PdfWriter constructor (1703)

Bug Fixes (BUG)
- 'DictionaryObject' object has no attribute 'indirect_reference' (1729)

Robustness (ROB)
- Handle params NullObject in decode_stream_data (1738)

Documentation (DOC)
- Project scope (1743)

Maintenance (MAINT)
- Add AnnotationFlag (1746)
- Add LazyDict.__str__ (1727)


[Full Changelog](https://github.com/py-pdf/pypdf/compare/3.6.0...3.7.0)

New Features (ENH)
- Extend PdfWriter.append() to PageObjects (1704)
- Support qualified names in update_page_form_field_values (1695)

Robustness (ROB)
- Tolerate streams without length field (1717)
- Accept DictionaryObject in /D of NamedDestination (1720)
- Widths def in cmap calls IndirectObject (1719)

[Full Changelog](https://github.com/py-pdf/pypdf/compare/3.5.2...3.6.0)