Update changelog.mdx

Author: mintlify[bot]

changelog.mdx

@@ -5,6 +5,41 @@ rss: true
 noindex: true
 ---
 
+<Update label="September 20 - September 26" tags={["Improvements"]} rss={{ title: "Weekly Updates", description: "Language support expansion, UI improvements, infrastructure enhancements, and Slack integration updates" }}>
+
+## Language support expansion
+
+- Added support for Romanian and Czech languages in the documentation interface
+- Enhanced localization capabilities with complete translation coverage for new languages
+- Improved language selector functionality across all themes
+
+## UI and user experience improvements
+
+- Fixed tab visibility issues on 404 pages to prevent incorrect active tab highlighting
+- Enhanced image handling with proper width and height attribute passing for non-optimized images
+- Improved 404 page layout and styling consistency
+
+## Infrastructure and performance enhancements
+
+- Set up security groups for PostgreSQL access via Tailscale for improved database connectivity
+- Enhanced GIF image processing by skipping costly Imgix auto-formatting to reduce processing time and bandwidth usage
+- Optimized image serving performance with special handling for animated content
+
+## Slack integration updates
+
+- Created comprehensive data models for Writer Slack User to Mintlify User mapping
+- Implemented user authorization system for Slack bot interactions
+- Added login message functionality with proper authentication flow guidance
+- Enhanced security with organization-level access control for Slack users
+
+## Bug fixes and reliability
+
+- Fixed contact email routing in dashboard settings for Assistant add-on requests
+- Improved error handling and user feedback in Slack integration workflows
+- Enhanced database schema updates for better user management
+
+</Update>
+
 <Update label="September 14 - September 19" tags={["Improvements"]} rss={{ title: "Weekly Updates", description: "GitLab integration enhancements, app router migration progress, authentication improvements, and bug fixes" }}>
 
 ## GitLab integration enhancements