Visual Studio tooling (e.g. XAML and WinForms Designers, app publishing tools) for WinForms and WPF development with .NET Core 3. 

Point to note that, Visual Studio 2017 version 15.9 would be the last/final release of Visual Studio 2017, as it has been designated as "Service Pack". Microsoft won't be releasing any further updates to it. 

A preview of UX and UI changes in Visual Studio 2019  

Visual Studio 2019 (version: 16.0.0 Preview 1) leaked online 

• Productivity and Performance improvements – Visual Studio is more responsive and usable, and projects load faster.
• Improved tooling to profile and understand your applications performance.
• Updated JavaScript and TypeScript tooling, including improved Vue.js and ESLint support, and right-click context menu productivity improvements.
• More C++ productivity improvements in IntelliSense, Code Analysis, and Just My Code debugging.
• Improved performance for Visual Basic integer manipulation.
• Azure Development improvements, including continuous delivery for Azure Functions, better experience managing secrets via Key Vault, and ability to configure Application Insights during initial site creation.
• More Library Manager features for managing Web Projects’ client-side library files.
• Mobile Development improvements such as faster Android incremental builds and inclusion of Xamarin.Essentials to facilitate building native apps. 

These are the customer-reported issues addressed in 15.7.3:

• VS2017 compiler creates broken debug build using Qt framework and generates 'Invalid address specified to RtlValidateHeap' error.
• Incorrect code generation for matrix multiplication.
• VS 2017 Update 7: Git History Codelens only showing entries for the past 6 months.
• UWP projects reference multiple NetStandard 2.0 dlls after 15.7.1 upgrade.
• Building C++ code in VS 15.7 with /std:c++17 breaks binary compatibility for std::_Ptr_move_cat.
• Visual Studio 15.7 stuck when opening XAML files.
• CMake configuration fails and generates message "C++ IntelliSense information may be out of date, generate the CMake cache to refresh".
• Unable to start second process for debugging.
• After update to Visual Studio 15.7.1, some test programs fail in start-up due to reading access violation.
• Missing compiler required member 'Microsoft.CSharp.RuntimeBinder.Binder.Convert'.
• Build fails after 15.7.0 update on older project using .NET 3.5 .
• Coloring, typing, tooltips and IntelliSense slow in F# in VS2017 editor.
• F# editing experience takes up to a minute for tooltips and dropdowns to display.
• Certain class member variable value are incorrectly read as zero.
• Attempt to open XAML file for the first time causes VS to sit with the "Opening the file ..." message for about 10 minutes before XAML file opens.
• Visual Studio slows down and freezes, creating work loss.
• The target "GetBuiltProjectOutputRecursive" does not exist in the project.
• Internal error with lambda C++17 after 15.7.1 update.
• UWP App is slow to return a stopped state in IDE.
• MSVC auto-vectorization produces incorrect code or incorrect results.
• Visual Studio closed debug a new instance project1, when a new debug new instance project2 has started.
• Latest update breaks "start without debugging" on multiple projects.
• UWP XAML is very very slow on open.
• XAML viewer freezes on 15.7.2 and 15.8.0 preview 1.1.
• Xamarin UI Test App project template missing.
• Xamarin project creation problem.
• Visual Studio crashes when creating new Mobile APP Xamarin.
• Unable to create Xamarin.Forms-Projects.
• Não consigo criar novos projetos Xamarin Forms - Can't create new projects Xamarin Forms.
• Blank project crash after update. 

Visual Studio 2017 15.8, meanwhile, will see the asynchronous background auto loading of extensions delayed until after Visual Studio startup and solution load are completed.