Avalonia

https://github.com/MonoGame/MonoGame (runs even on consoles, which is rare for open source game frameworks and engines) https://github.com/SubtitleEdit/subtitleedit https://github.com/jellyfin/jellyfin https://github.com/AvaloniaUI/Avalonia https://github.com/bitwarden/server https://github.com/unoplatform/uno https://github.com/files-community/Files https://github.com/NickeManarin/ScreenToGif https://github.com/DevToys-app/DevToys https://github.com/d2phap/ImageGlass https://github.com/ShareX/ShareX https://github.com/duplicati/duplicati https://github.com/OpenRA/OpenRA https://en.wikipedia.org/wiki/Ryujinx https://sourceforge.net/projects/keepass/ https://github.com/orchardcms https://github.com/piranhacms/piranha.core https://github.com/umbraco/Umbraco-CMS

Avalonia left the .NET Foundation a year ago. https://github.com/AvaloniaUI/Avalonia/discussions/14666

MS UI has been a mess for years. They just can't pick a paradigm to run with apparently, so people just fall back to good ole' Winforms. That being said, check out Avalonia: https://avaloniaui.net/ and https://github.com/AvaloniaUI/Avalonia Cross-platform, open source, MVVM & reactive. A breath of fresh air.

They seem to be using this framework: https://github.com/AvaloniaUI/Avalonia Avalonia aims at compatibility with Windows Presentation Framework (WPF) XAML. The web platform is explicitly supported: https://avaloniaui.net/platforms#wasm. The VB Form model must be implemented on top of this. This is for the UI part. Now for the code part, the dotnet toolchain has supported WebAssembly (wasm) generation for some time: https://devblogs.microsoft.com/dotnet/extending-web-assembly... I suppose the C# code is translated to MSIL then wasm.

Luckily, for the project of this type, you can use SkiaSharp (which is awesome) or simply implement a rendering back-end that targets OpenGL/Vulkan/DX/Metal. There are rich binding libraries with low/zero overhead to do so like TerraFX or Silk.NET or you can just do it directly. For example, Avalonia implemented Vulkan back-end some time ago, no C or C++ required: https://github.com/AvaloniaUI/Avalonia/pull/12737 Even then, you are absolutely not married to any of these GUI frameworks, but if are targeting desktop, then Avalonia offers great user experience.

I'm talking from memory (tried opening the FluentAvalonia sample so the styling may have affected it), but I will try again later and post results hopefully. Others found high CPU usage too, but not as high as 70% (more like half that). https://github.com/AvaloniaUI/Avalonia/issues/11070

Production user here. I've found no money "gotchas". They're above reproach. In fact, I've received considerable free support from their devs on GitHub Issues [1]. The Avalonia business model is based on selling XPF, which runs WPF (Windows-only) apps on other platforms. That's very interesting to big corps with existing codebases. See my comment [2] [1] https://github.com/AvaloniaUI/Avalonia/issues [2] https://news.ycombinator.com/item?id=39246988#39249128

Do you mean accessibility? I did notice disappointing non-native-like behaviours when I tried typing in an AvaloniaUI textbox but I'm hopeful they will manage to solve that and other issues. For example, pressing a space will always introduce a new item in the undo/redo history [0] which isn't how native textboxes work. [0] https://github.com/AvaloniaUI/Avalonia/blob/942901c624df73b7...

Not my comment, but relevant here "The problem with compiling Skia to WASM is you'll lose any benefits of hardware graphics acceleration on the device." (From https://github.com/AvaloniaUI/Avalonia/discussions/6831#disc... )

It's a bit of a hit and miss as of today. CLI, back-end and natively compiled libraries (think dll/so/dylib or even .lib/.a - you can statically link NAOT binaries into other "unmanaged" code) work best, GUI - requires more work. Avalonia[0] and MAUI[1] have known working templates with it, but YMMV. [0] https://github.com/lixinyang123/AvaloniaAOT / https://github.com/AvaloniaUI/Avalonia/ [1] https://github.com/dotnet/maui (try out with just <PublishAot>true</PublishAot> in csproj - it is known to work e.g. on iOS)

Showcase of apps built with avalonia: https://github.com/AvaloniaUI/Avalonia#showcase Saw this update for Avalonia that I wanted to share, since the prospects of the new features are exciting. I've made a couple of small-medium GUIs using it and the experience has been nice. I use it with F# and an elmish functional-reactive library: https://avaloniacommunity.github.io/Avalonia.FuncUI.Docs/ I also develop on and primarily for linux (pop_os, but use my applications on macos as well). It's not perfect, and a commonly cited criticism is that the documentation could be more robust, but in the sea of GUI frameworks this is my favorite target if electron is not viable (still IME the most mature and supported).