The Blog Application 9.15.3 has been released. This release fixes a regression introduced in 9.15 that broke Blog RSS feeds when filtering by category.
Additionally, several other bugs and improvements were addressed, for example, the blog posts containing a dot in their name do not break anymore the pinned-posts feature.
We also added support for legacy category locations, made migration optional so blogs continue to work with legacy assignments, and made the missing-categories notification in the post editor configurable (new property to enable/disable the category selection check).

Check the full list in release notes.