Qubes No Longer Recognizes External Monitors

[mpenterp...@gmail.com]

System:
-Qubes current (4.0rc5 - I guess it's just 4.0 Stable now?)
-Thinkpad P70 with Skylake i7
-Kernel Flags: i915.alpha_support=1 rd.blacklist.drivers=nouveau nouveau.modeset=0
-Bios:
--USB UEFI BIOS Support: Enabled
--UEFI/Legacy Boot: UEFI Only
--Secure Boot: Disabled

Previously: 4.0rc4 installed
-Plug in External Monitor via HDMI or MiniDP
-XFCE Display manager launches and external displays are configurable
-Displays show up in Display Manager and xrandr

Now: Fresh Install of Qubes 4.0rc4, applied qubes updates to get 4.0rc5/4.0 Stable
-Plug in External Monitor via HDMI or MiniDP
-Qubes Display manager launches
-No monitors are available except built-in are available on Display Manager
-xrandr shows only built-in monitor

Any ideas how I can get my external monitors back?

Thanks!

[awokd]

It's odd the display manager is automatically detecting them to launch,
but not showing them. Do they work if you plug them in before powering on
the system and booting Qubes? Check the Xorg logs for errors too.