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Sitefinity Release Notes

Sitefinity CMS 15.4.8623 (Product Update)

January 27, 2026

What's new:

  • Sitefinity AI Assistant: New configuration of the chat widget is available, powered by Progress Agentic RAG (576523)

    Documentation for MVC, ASP.NET Core renderer, and NextJs renderer

  • Sitefinity AI Assistant: Support for default language is added (562526)

    Learn more...

  • Tools added to the AI quick actions menu in Rich-text editor (formatting styles, unordered list, ordered list) (552018)

What's fixed:

  • Site Sync: Sync email templates along with forms (575460)
  • Next.js Renderer: Cannot read properties of null (reading 'contentItemModel') when saving the widget (571401)
  • Next.js Renderer: Hidden form fields are not hidden when in a layout section with columns (576582)
  • Custom role with permissions to manage users, roles and permissions is unable to assign roles to users (571872)
  • Admin App: The Compare Translation sidebar breaks for dynamic content items when a language is deleted or disabled (569129)
  • Preview link for content items does not work for Editor (Non-Admin) role when saving as Draft (572401)
  • AI Assistant: Selecting the created AI assistant does not populate a greeting message and name value (554577)
  • Message Templates: Locked Message Template cannot be unlocked from the UI (563345)
  • Invalid access token is obtained from refresh token with expired backend user session (572704)
  • Duplicate content items are generated when scheduled publishing is used along with Site Sync. The original items are not removed on the target environment (578633)
  • ASP.NET Core Renderer: AI assistant widget improvements in Page editor (561230)
  • OData: Duplicate content Items returned with paged results (433093)
  • Taxonomies: Use AI suggestions is not working when the existing tags are too large count (578273)
  • Fixed an issue where a document processing failure could cause a deadlock, blocking the processing of all documents (576163)
  • Search: Inconsistencies in search index when using site-specific classification (576930)
  • MVC Image widget throws exception when the selected image is deleted (574436)
  • Required custom DateTime field value is not initially persisted (576743)
  • Site Sync: Pages do not appear for sync to the target environment (in multilingual setup) (576758)
  • ASP.NET Core Renderer: Image widget displays original image when no thumbnail is available (578073)
  • Admin App: After upgrading to Sitefinity 15.4, a 'Default.BackgroundTasks' error occurs in the browser console (575463)
  • ASP.NET Core Renderer: Multiple images in Content blocks break subsequent SVG icons (574817)
  • AI service allows creating new taxa when Allow creating new taxa setting is set to false (578630)
  • Search index file locking issue in NLB setup, causing errors and affecting Site Sync (578665)
  • Intermittent error after deleting a form causing exception in the backend (579426)
  • Intermittent issue with stale output cache item, potentially caused by delay of L2 cache invalidation in NLB communication (578444)
  • Content blocks do not load or work when used in sub-application mode (572384)
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