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

Main: Fixed issue when VBoxSVC could become unresponsive if Extension Pack was not installed (bug #21167)

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

macOS hosts: Fixed VM crash when the guest tries to access a microphone or webcam

Windows host: Shared Clipboard: Fixed issue when only 4Kb of host clipboard buffer was accessible to guest (bug #21149)

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)

Windows hosts: GUI: Fixed missing Qt libraries for vista style and sql driver (bug #21155)

GUI: Fixed a glitch in the log viewer which was causing wrong log file to be saved (bug #21156)