I've searched for bugs related to the specific problems I've been having, and I've not been able to find anything that describes what I'm seeing.

I have an HP EliteBook 840 that also comes with an UltraDock, to which I've plugged-in two external monitors and I use in conjunction with the built-in laptop display.

Issue #1: I use LUKS to encrypt my disk, and when I first start up the computer, after choosing the kernel to boot into in GRUB, the GUI prompt for the LUKS passphrase shows-up on the middle monitor, not the laptop's built-in display.  I don't mind this when I have multiple monitors plugged-in, but when I boot-up without the external monitors, such as when I'm unplugged from the UltraDock, I now get NO GUI prompt for the LUKS passphrase.  I can enter it, and I can see a text prompt if I hit ESC.  I suspect its attempting to display on the now phantom, unplugged monitor.  Note, it was never plugged-in during this cycle.  The problem is, I don't even know what's instructing LUKS or the GUI prompt to display on any monitor, so I don't know where to go to debug this.

Issue #2: When I undock my laptop while logged-in, Gnome Shell just crashes.  When I redock after the laptop has been started when unconnected, one of the two external monitors start-up (the one connected by VGA), but not the one connected by a DisplayPort connection.  And, recently (but not when I first started using this laptop with the dock, which was about a month ago), now when I start-up with the laptop docked and both external monitors connected, both external monitors will be active, but the built-in display will show nothing.  Gnome Shell reports the built-in display is active, but will not display anything unless I deactivate it and reactivate it via the settings "Displays" utility.

Issue #3: The monitor connected via DisplayPort display significant tearing and delay on the upper-right half of the screen in the form of a triangle taking-up half of the screen.  Reading about displayport and tearing issues, I guess the idea that these were resolved in the past.  I don't know if this is the same or something different.

I don't mean to use devel as a bug reporting venue, but I think these issues are either related or I just don't know how to address them to make significant progress to fixing them.  Any guidance is more than welcome.  Thanks!

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