Feature Improvements and bug fixes:

• VMM: fixed reboot hang of 32-bit Windows SMP guests 
• VMM: proper Math Fault handling with certain legacy guests 
• VMM: fixed a Guru Meditation VINF_EM_TRIPLE_FAULT on older CPUs that don't support MSR-bitmaps (VT-x only)
• GUI: fix 3D overlay window re-parenting issue when VM goes to full screen mode on X11 hosts.
• GUI: fix occasional loss of focus in full-screen mode on X11 host systems (4.3.16 regression)
• GUI: Mac OS X: wizards should have Cancel button
• GUI: added a global option to prevent automatic raising of the new window by mouse move with multi-screen guests 
• API: accept remote display port 0 as the default RDP port (bug #8534)
• VBoxManage: fixed crash when executing showvminfo command under certain circumstances 
• ACPI: fixed occasional Guru Meditations in ACPI timer code (4.3.18 regression)
• EFI: improved performance of IDE disk access
• EFI: fixed a bug in the EFI video driver which prevented Windows to boot in UEFI mode 
• EFI: properly announce the amount of RAM for big VMs 
• Storage: fixed a crash under certain circumstances when a medium was ejected from a drive attached to the SATA controller without inserting a new medium before pausing or closing the VM (4.3.16 regression)
• Storage: fixed an interrupt acknowledge issue causing hanging guests or slower I/O (4.3.18 regression)
• Storage: fixed broken resume after the VM was suspended due to a full disk if host I/O caching is used
• Storage: fixed a Guru Meditation under certain conditions when using the DevLsiLogic controller with VMs running in raw mode (4.3 regression)
• Guest Control: fixed a bug which might lead to a crash during recursive copy
• SDK: Java COM bindings fixes
• iPXE: enable the HTTP download protocol 
• Runtime: do not use a fixed stack size creating temporary threads during initialization 
• Windows hosts: fixed more startup problems on certain Windows hosts due to conflicts with anti-virus software; better error reporting (4.3.14 regression)
• Windows hosts: fixed DirectSound host audio failure under certain conditions 
• Windows hosts: fixed additional cases of 4.3.14 regression whereby AltGr stopped working for some people 
• Windows Additions: preserve guest monitor layout when resizing Windows 7 or newer guests
• Linux Additions: Linux 3.18 compile fixes