Changelog for python3-markdown: 3.10.2 -> 3.10.3
Source: docs/changelog.md

## [3.10.3] - 2026-07-30

### Fixed

* Fix `SetextHeaderProcessor` regex to prevent mixed `=` and `-` chars in setext-style headers (#1606).
* Add AI Policy to Contributing Guide.
* Officially document all included extensions as being in maintenance mode.
* Link the Extension API documentation to the API Reference (#1612).