Hi there, I couldn't see this covered elsewhere and hit a wall trying to fix it. I love tinkering with Linux but some days it takes the... Software: Running ElementryOS 5.1 (latest stable build), inside VirtualBox 6.1 (latest stable build), with VirtualBox Guest Additions installed (see below). Hardware: I have a external monitor (HP 27f 1920x1080 @ 60hz) connected to the host (running macOS 10.15.5). Problem: Everything is sweet (ElementryOS working perfectly out of the box and looking great). Then I install VirtualBox Guest Additions and it immediately correctly auto-resizes the screen to 1920x1080. EXCEPT after a "virtual power cycle" shtdown and reboot, immediately after the GUI login screen I get an idle blank black screen with no functionality whatsoever, but I can still see the cursor... (And yes – I can see the GUI login screen okay so X is working fine, and no – nothing happens if I leave it for ages...). All quite frustrating as ElementryOS looks great and it is soooo nearly working perfectly. Kinda reminds me of the good old PowerPC days playing with xorg.conf for days... Ahem. VirtualBox log dump attached (and please forgive the brain dump!).