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Ubuntu Focal Desktop Multiple Monitors

Hey everyone, Linux noob here. Since upgrading from Bionic to Focal, my ability to support multiple
monitors has effectively disappeared. I’ve seen similar questions asked, but I’ve yet to find a workable solution. System info and Xrandr outputs below

  • HP Revolve 810 G1 closed lid
  • Intel Core i5-3437U CPU @ 1.90GHz
  • 2x Dell U2415 monitors connected to a HP slim docking station with 2x DP outputs (I believe they’re DP 1.2)
  • Intel® HD Graphics 4000 (IVB GT2)
  • Ubuntu 20.04.1 LTS
  • GNOME 3.36.3 X11
  • X.Org version 1.20.8

00:02.0 VGA compatible controller: Intel Corporation 3rd Gen Core processor Graphics Controller (rev 09)  
    DeviceName: 64  
    Subsystem: Hewlett-Packard Company 3rd Gen Core processor Graphics Controller  
    Kernel driver in use: i915  
    Kernel modules: i915  

Screen 0: minimum 320 x 200, current 1920 x 1200, maximum 16384 x 16384  
LV-DS-1 connected (normal left inverted right x axis y axis)  
VGA-1 disconnected (normal left inverted right x axis y axis)  
HDMI-1 disconnected (normal left inverted right x axis y axis)  
DP-1 connected primary 1920x1200+0+0 (normal left inverted right x axis y axis) 518mm x 324mm   
   1920x1200     59.95*+  
HDMI-2 disconnected (normal left inverted right x axis y axis)  
HDMI-3 disconnected (normal left inverted right x axis y axis)  
DP-2 disconnected (normal left inverted right x axis y axis)  
   1920x1080     60.00  
DP-3 disconnected (normal left inverted right x axis y axis)

  *-display                 
       description: VGA compatible controller
       product: 3rd Gen Core processor Graphics Controller
       vendor: Intel Corporation
       physical id: 2
       bus info: [email protected]:00:02.0
       version: 09
       width: 64 bits
       clock: 33MHz
       capabilities: msi pm vga_controller bus_master cap_list rom
       configuration: driver=i915 latency=0
       resources: irq:32 memory:d0000000-d03fffff memory:c0000000-cfffffff ioport:2000(size=64) memory:c0000-dffff

It seems like there an awareness of DP-2, but no matter how I connect the cables or which cables I use (directly to dock, dock to laptop’s built-in DP output, or daisy-chaining), nothing changes, and my second monitor is black.

I know multiple displays are supported because when I open the lid I get multiple displays (LVDS and DP-1). Let me know if there’s more info or troubleshooting steps I need to take.