Uno Platform 6.3: Faster Rendering, .NET 10 Preview, VS 2026 Ready

With over 128 issues closed, Uno Platform 6.3 continues to raise the bar for cross-platform .NET development. This release aligns with Microsoft’s latest tooling while polishing the features you use every day and pushing Hot Design further as the only visual designer for cross-platform .NET applications.

Uno Platform 6.3 highlights

.NET 10 Preview support – Test drive Microsoft’s latest SDK and runtime today.
Visual Studio 2026 ready – Full support for the new .slnx format and side-by-side compatibility with VS 2022
WebAssembly breakthrough – Image decoding moved to WebWorkers means your galleries finally scroll smoothly
TabView refined – The reliability LOB apps demand, with new sizing modes and non-closable tabs
Hot Design productivity – Search the elements tree instantly, toggle visibility to hide design-time clutter

Blockquote Styles

⚠️ Note: .NET 9 remains the stable target for production apps. .NET 10 support is currently in RC and should only be used for testing and evaluation.

⚠️ Note: Extensions and plugins for all supported IDEs have been updated with important fixes. Make sure you’re on the latest version to stay compatible and keep your workflow productive with Uno Platform.

Uno Platform 6.3 Adds .NET 10 Preview Support

Uno Platform 6.3 introduces support for .NET 10 RC 1 alongside the existing support for .NET 9 (the current stable release), giving you the flexibility to choose between established stability, versus early access to the latest runtime features such as CoreCLR with Android.

When creating a new project with the Uno Platform wizard, you can now target .NET 10 directly:

				
					<TargetFrameworks> 
net10.0-android; 
net10.0-ios; 
net10.0-windows10.0.19041; 
net10.0-desktop; 
net10.0-browserwasm; 
</TargetFrameworks>

Reminder: .NET 10 and Uno Platform support for it are still in Preview. These targets are for testing and early feedback only, not production apps. For stable production apps, continue to use .NET 9 targets until .NET 10's official release.

👉 A migration guide for Uno Platform .NET 9 → 10 can be found here.

To validate your environment against preview runtimes, uno-check includes a --pre-major flag.

				
					uno-check --pre-major

📝 More on Uno-check preview support

Uno Platform 6.3 Removes .NET 8 Support

While .NET 8 itself remains a Long-Term Support (LTS) release supported until November 2026, the .NET MAUI 8 mobile workloads reached end of support in May 2025. To maintain alignment with supported runtimes, Uno Platform 6.3 has removed .NET 8 support.

If your projects are still on net8.0, now is the time to migrate:

Move to .NET 9 for a stable, supported runtime

Use our migration guide from .NET 8 → 9 to update your projects

⚠️ Note: Uno Platform 6.2 will not be updated further. The recommended path forward is to migrate to a later version.

Visual Studio 2026 Compatibility

This release brings preview support for Microsoft’s latest runtime and full compatibility with Visual Studio 2026, including its new .slnx solution format that’s finally human-readable.

Uno Platform’s VS extension has been updated to work seamlessly with VS 2026’s changes:

The new .slnx format replaces the cryptic .sln files we’ve been dealing with for decades. It’s cleaner, less verbose, and you can actually understand what changed in your git commits

Updated project system support ensures all Uno Platform features work as expected in the new environment

Side-by-side compatibility means you can keep VS 2022 running alongside 2026, no need to migrate your entire team at once

Get the extension from the Marketplace →

⚠️ Note: Extensions and plugins for all supported IDEs have been updated with important fixes. Make sure you’re on the latest version to stay compatible and keep your workflow productive with Uno Platform.

Update your IDE extensions: Visual Studio, Rider, VS Code.

⚠️ Note: Use Visual Studio 2026 Insiders version 18.0.0 [11104.47] or later to ensure compatibility with the latest stable Uno Platform extension.

WebAssembly Rendering Performance

Image-heavy apps on WebAssembly are now significantly smoother. In Uno Platform 6.3, image decoding is moved off the UI thread and into WebWorkers, finally making scrolling through galleries, feeds, and dashboards feel more responsive.

What this means for your apps:

Parallel decoding – Multiple images decode simultaneously while the UI thread stays free for rendering and user input

Higher throughput – More images processed per second means faster perceived load times

Smoother interactions – No more UI stalls when users scroll through image-heavy content

If you’ve built Uno Platform WebAssembly apps with heavy image workloads before, the difference is immediately noticeable, the stuttering and freezes that could have impacted image lists are gone. This is especially impactful for LOB apps with data visualization dashboards or consumer apps with media galleries.

Curious how the new Wasm 3.0 release changes the .NET story in the browser? Check out our breakdown: Wasm 3.0 for .NET developers.

TabView Improvements

TabView in Uno Platform is now more consistent and reliable across platforms. In 6.3, everyday behaviors have been polished so your tabbed interfaces feel seamless.

Consistent tab rendering across all targets
Enhanced tab selection reliability
Improved drag & drop UX

This is a big win for line-of-business (LOB) apps, where tabbed layouts are essential for dashboards, data entry, and multi-document interfaces. Developers have been asking for smoother tab behavior in these scenarios and 6.3 delivers.

Beyond fixes, TabView also gets new flexibility:

Customize tabs visually in Hot Design: change headers, backgrounds, or icons and see them update instantly.

Reorder tabs both in Hot Design and at runtime, so developers and end-users can organize layouts the way they need.

Non-closable tabs: protect essential tabs (like “Home”) so they’re always available.

New sizing modes: choose equal sizing, compact, or size-to-content so your tabs don’t waste space when many are open.

📺 Want a deeper dive? Watch Martin Zikmund walk through TabView in our recent Hot Design AMA:

Hot Design Enhancements

Visual design isn’t just about looks, it’s about iteration speed, reducing rebuild loops, and making UI building more productive.

Hot Design, part of our premium Uno Platform Studio offering, has quickly become a go-to tool for Uno Platform developers, making UI building faster and more iterative. If you’ve used Blend or the WinForms designer, the workflow will feel familiar but modernized for today’s cross-platform apps.

In Uno Platform 6.3, Hot Design gets better with:

Search in the elements tree lets you instantly jump to any control in complex layouts, saving you from expanding dozens of nodes manually.

Inspect more properties like the pane for SplitView and NavigationView

Together, these updates make Hot Design more practical for real-world projects and keep pushing it toward the level of productivity developers expect from a modern visual designer.

Missed our latest Hot Design AMA? Watch it here

➡️ Upgrading to Uno Platform 6.3

Upgrading to Uno Platform 6.3 ensures your apps are aligned with the latest .NET runtimes, IDE extensions, and tooling. The recommended target is .NET 9, with the option to experiment with .NET 10 RC 1 for early testing.

Here’s how to make the transition smooth:

Update your IDE extensions

Make sure you’re on the latest Uno Platform extensions for all supported IDEs:

Visual Studio
Uno Platform Add-In 2022

VS Code
Uno Platform VS Code Extension

JetBrains Rider
Uno Platform Rider Plugin

Migrate your project to Uno Platform 6.3

Follow the official migration guide to update your project configuration and dependencies:

👉 Migrating from previous releases

Target the latest .NET runtime

Make sure your app’s TargetFramework in the project file is set to .NET 9 (or .NET 10 RC 1 for early adopters):

Known Issues
For an up-to-date list of known issues when using .NET 10 with Uno Platform, please refer to our Health Status Page.

Get Started

With new features like .NET 10 Preview, Visual Studio 2026 support, WebAssembly performance boosts, and Hot Design enhancements, there’s never been a better time to start building with Uno Platform.