This is a maintenance release. The following items were fixed and/or added: Known issue: VMs having more than one vCPU configured will not work properly on macOS Catalina due to an unknown memory corruption issue. Either lower the number of vCPUs to 1 or upgrade to BigSur or later where the issue does not occur macOS hosts: Added workaround for a bug in the Hypervisor framework on Catalina causing VERR_NEM_MAP_PAGES_FAILED errors when starting a VM. (bug #21128) macOS hosts: Re-introduced support for internal networking, this is considered a bit experimental still Linux Guest Additions: Introduced initial support for kernel 6.1 Linux Guest Additions: Fixed issue when VBoxClient seamless service caused a crash of some X11 applications (bug #21132) GUI: Fixed a glitch in the log viewer which was causing wrong log file to be saved (bug #21156) This is a major update. The following major new features were added: Virtual machines can be fully encrypted now, including the VM config logs and saved states (CLI only for now) OCI: Cloud virtual machines can be added to Virtual Machine Manager and controlled as local VMs OCI: Cloud networks can now be configured via Network Manager tool same way as it is done for Host-only and NAT networks GUI: Added a new utility similar to "top" or "resource monitor" which lists peformance statistics (CPU usage, RAM usage, disk I/O rate, etc.) of running guests GUI: Reworked the new vm wizard to integrate the unattended guest OS installation and to have a more streamlined work flow GUI: Added a new help viewer widget which enables the user manual to be navigated and searched GUI: Adding new notification center unifying most of running progresses and error reporting around the GUI GUI: Improved theme support on all platforms. Linux and macOS use native engine while for Windows host it is separately implemented. GUI: Large icon update. Audio recording: Now using Vorbis as the default audio format for WebM containers. Opus is no longer being used. Audio: Added "default" host driver type to make it possible to move VMs (appliances) between different platforms without the need of changing the audio driver explicitly. When the "default" driver is selected, the best audio backend option for a platform will be used. This is the default for newly created VMs. Guest Control: Implemented initial support for automatic updating of Guest Additions for Linux guests Guest Control: Implemented ability to wait for and/or reboot the guest when updating Guest Additions via VBoxManage VBoxManage: Added Guest Control "waitrunlevel" sub-command to make it possible to wait for a guest to reach a certain run level Windows hosts: Added experimental support of running autostarted VMs in session 0, to allow running VMS even when a usser is not being logged in (disabled by default, please consult the manual) macOS host: Dropped all kernel extensions. VirtualBox relies fully on the hypervisor and vmnet frameworks provided by Apple now. At the moment the implementation lacks "Internal Networking" functionality. This will be provided at a later date. macOS host: Providing a Developer Preview package for systems with an Apple silicon CPU. This is unsupported work in progress, and is known to have very modest performance. Linux Guest Additions: Reworked guest screen re-size functionality, added basic integration with some of guest Desktop Environments Devices: Implemented new 3D support based on DirectX 11 (and DXVK on non Windows hosts) Devices: Added virtual IOMMU devices (Intel and AMD variant) Devices: Added virtual TPM 1.2 and 2.0 devices Devices: The EHCI and XHCI USB controller devices are now part of the open source base package EFI: Added support for Secure Boot Debugging: Added experimental support for guest debugging through GDB and highly experimental support for guest debugging through KD/WinDbg In addition, the following items were fixed and/or added: OCI: Cloud networking functionality is enhanced for local VMs, now local VMs could be connected to cloud networking GUI: Improved behavior of the virtual machine list and various VM related tools in case multiple items are selected GUI: On available platforms, added a new option to disable the host's screensaver GUI: Reworked global preferences, machine settings and the wizards to improve stability and usability GUI: Improving mouse handling in multi-monitor case on X11 platform GUI: Medium enumeration engine was reworked to improve permormance GUI: NAT Network stuff was moved from global preferences to global Network Manager tool GUI: Extension Pack Manager was moved from global preferences to global tools GUI: Improved overall accessibility GUI: Migrating to recent Qt versions.