Umbraco

🚨 [Breaking change]: Removal of `BackOfficeDevelopment` runtime mode and `InModelsBuilder` models builder mode due to deprecation of Razor runtime compilation support in .NET

Andy Butland announces that Razor run-time compilation is now obsolete, urging against its use in production. This change affects Umbraco features like the BackOfficeDevelopment runtime mode and InMemoryAuto models builder, which will be removed in Umbraco 19. Users are advised to edit templates as .cshtml views and utilize dotnet watch for hot reload.

📰 Introducing the Autumn Contribution Challenge 2025

Sebastiaan Janssen announces the Autumn Contribution Challenge, encouraging year-round contributions to the Umbraco community. Participants can submit code samples, blog posts, and ideas to enhance a new community website's "Developer" section. The initiative fosters collaboration, visibility, and learning, culminating in a site launch that showcases contributors' work.

🚨 [Breaking change]: Extension Manifest Type Architecture + Constants/Modal Tokens/Types moved to their package

In Umbraco 15, components have been decentralized into their respective packages, altering import paths and enabling better extension capabilities. Developers must update their TypeScript configurations and imports to accommodate the new structure, utilizing the global UmbExtensionManifest for extension types. This change enhances flexibility for package developers but introduces breaking changes.

🚨 [Breaking change]: Settings will change from Arrays to ISet<T>s in Umbraco 16