Sitefinity Release Notes

What’s new

• This product update introduces a new framework that enables you to create and use custom AI agents in your Sitefinity CMS backend. The framework allows custom AI agents to be configured through prompts, settings and tools, and be used consistently in parallel with the built-in AI agents. (583750)
  Learn more...
• The scope of the built-in Sitefinity AI agents (Brand voice Agent, SEO Agent) is now extended to support Pages, in addition to content items. The AI agents are enabled to analyze and provide improvement suggestions for your page-level experiences. (584739)
  Learn more about Brand voice Agent...,Learn more about SEO Agent...
• Next.js middleware is now refactored to support automatic detection of externally rendered pages. The updated Next.js proxy file must be manually copied over and must be enabled throughSF_PROXY_BY_DEFAULT="true"env variable.
  Learn more...
• You can now use JSON filter expressions in the Search Box widget to limit the content displayed in search results.
  Learn more... (ASP.NET Core),Learn more... (Next.js)

Third-party libraries update

Next.js Renderer:

• next →16.2.6
• react →19.2.6
• react-dom →19.2.6

IMPORTANT: Sitefinity CMS 15.4.8631 updates the Sitefinity Next.js Renderer to Next.js 16.2 and React 19.2. This framework update is a breaking changefor customers using Next.js based frontend and upgrading projects from Sitefinity 15.4 versions earlier than 15.4.8630.
To maintain compatibility, affected customers are required to apply some necessary changes manually in the Renderer.Learn more...

What's fixed

• Site Sync: Page cannot be published after cancelling sync operation of single item (589286)
• ASP.NETCore Renderer: Page cannot be edited with error "The provided widget metadata was not correct" (589085)
• ASP.NETCore Renderer: A/B testing personalized widgets disappearing randomly (579831)
• ASP.NETCore Renderer: An exception is thrown when proxying requests with headers that contain non-ASCII characters (589949)
• ASP.NETCore Renderer: Sections with no suitable available data prevent the rendering of other sections (583694)
• Next.js Renderer: Media items cannot be deselected when created as SdkItem (588048)
• When adding links to the same document in separate Content blocks, the link in the second Content block does not resolve correctly (577179)
• Pages: When creating/updating a Page Title field, carriage return characters are not stripped on save (589401)
• Upgrade: PagesConfig fails to initialize when DecJsClient Path and/or DebugPath have been changed to an Embedded resource (590371)
• Misleading behavior when ordering Classifications in the backend (590371)
• Authentication: In multisite, users authenticated from external providers with site-specific roles cannot log into the backend (587712)
• When a project hosted in Azure is initializing, there are SQL timeout errors related to 'sf_taxonomies' table with a multilingual setup (590287)
• Deadlock on startup between 'AIServicesConfig' and 'SearchConfig' under concurrent first-request load (590368)

API and breaking changes

• Telerik.Sitefinity.Services.Search.FilterOperator.LesssThanOrEqualsis renamed to Telerik.Sitefinity.Services.Search.FilterOperator.LessThanOrEquals.