- A new flexible and virtualized list control, called TControlList. This new VCL control, designed as a high-performance control for very long lists, provides a modern look and feel, complete with custom UI configuration options allowing controls placed in each list item
- The second new VCL control is a TNumberBox control, a modern looking numeric input control. The control supports the input of integer numbers, floating point numbers with a given set of decimal digits and proper formatting, and currency values, even allowing expression evaluation
- Integrated IDE support for Microsoft’s newly recommended Windows application packaging format, MSIX, for Microsoft Store and Enterprise deployment; MSIX support incorporates the technology previously known as Desktop Bridge, and it’s one of the pillars of Microsoft’s Project Reunion
- Numerous enhancements and updates to the Konopka Signature Visual Control library (KSVC) for better integration with VCL styles. The new version of KSVC is available as a free addon for update subscription customers in the GetIt Package Manager
- The TEdgeBrowser VCL component introduced in 10.4 (a wrapper around the Windows 10 Chromium-based Edge WebView2 control) has been updated with support for the GA version of Microsoft’s WebView2 control and its SDK and now offers enhanced support for file cache management

- Compared to the previous versions, in 10.4.2 LSP adds many new features for Error Insight: the editor now shows colored underlines for hints and warnings as well as errors, meaning you can see potential important issues in the code editor (both Delphi and C++)
- There are also significant improvements to code completion in the uses clause, improvements to parameter completion, improvements to ctrl-click navigation’s understanding of the code including being able to ctrl-click on the inherited keyword, improved support for packages; and a large number of other improvements
- For C++, several important quality improvements have been implemented in LSP, addressing issues like international characters, indexing, and more
- A new style called Mountain Mist, echoing classic IDE colors
- Many enhancements to improve common developer activities in the IDE
- Improved IDE responsiveness, with a new progress dialog that shows what the IDE is doing during a lengthy operation, such as opening a large project group
- We have updated the library path management, and added the ability to convert paths to and from absolute paths to using environment variables in the path
- Updated Migration Tool with an extended list of settings and 3 preset configurations to choose from, plus the option to include additional configuration files
- New Low Code App Wizards for FireMonkey: these wizards, which will soon be available via GetIt for subscription customers, allow RAD Studio developers to quickly build a functional multi-screen application from scratch, by specifying a number of parameters through a wizard interface
- RAD Studio 10.4.2 supports silent, automated installations of Delphi, C++Builder and RAD Studio with no UI interaction

Expanded FireMonkey Platforms Support

- Delphi 10.4.2 includes support for deploying and debugging on version 11 of Android and significant improvements for deployment to the App Bundle format, required by Google’s Play Store along with the 64-bit app support
- Delphi developers can target macOS 11 Big Sur with Intel-based 64-bit applications using the FireMonkey framework, targeting the macOS App Store, or distributing their macOS apps locally or through their own website
- RAD Studio 10.4.2 provides support for building iOS 14 App Store ready applications in Delphi and C++, targeting the iOS 14 SDK, and debugging on iOS 14 devices

New Delphi and C++ Features

- Delphi compiler performance improvements obtained by implementing over 20 different compiler optimizations, with compilation time reduced to a fraction of what was in previous 10.4 releases for some large customer applications
- C++Builder 10.4.2 introduces a significant improvement addressing memory usage in the Win64 linker, including a new technology to greatly reduce the amount of data the linker needs to process. It does this by splitting the debug information to separate files (known as ‘split DWARF’)
- The new release sees a large overhaul of the C++ exception handling system, both within a module and cross-module; this includes C++ language exceptions, SEH, and OS exceptions
- The C++ RTL includes the latest version of the Dinkumware STL, and several more key open source C++ libraries will be made available in GetIt