[radeon] Dual screens started blinking from blank to another type of blank for =<1 second each state

I've just updated to 22.04 on 3x boxes: 2x laptops and 1x tower. Laptops went well as they are standard running wifi (note to self: next time upgrade one using a USB docking station+as many externally attached devices as possible should prove in a quite pleasurable end-user experience)

For the tower: this is the dual-screen portrait system I have been opening up defects for months now. Same config too. Anyways, after I rebooted the overall booting process happened pretty well until TTY7 tried kicking it and totally failed doing so hence rendered my system totally broken.

The behavior of my screens is that they started blinking from blank to another type of blank for =<1 second each state. But during one of those states there seemed to be Wayland as I could just see the mouse cursor fly around when activated.

Accessing other TTYs was also impossible as even though pressing CTRL+ALT+F2|F3|etc would indeed display a login prompt that within that same blinking instant that it had altered back to only that blinking cursor symbol(_) at the top-hand-left.

That behavior held true for all TTYs.

Pressing the power button did showed up the UM symbol alongside standard shutdown routine happened OK.

Solution was: unplug one of the two monitor and automagically jammy's login screen popped up.

If I replug that 2nd monitor while I am inside a working TTY7 session then the same (original) problem happens in which I cannot use any of the screens and when I re-unplug one of the two screens again I am re-back again at the jammy login having lost the current session that I had.

Both of my screens are the same model and both use HDMI.

I have attached my ~/.config/monitors.xml
---
ProblemType: Bug
ApportVersion: 2.20.11-0ubuntu82
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC1: dd 3464333 F.... pulseaudio
 /dev/snd/controlC0: dd 3464333 F.... pulseaudio
CasperMD5CheckResult: unknown
CurrentDesktop: MATE
DistroRelease: Ubuntu 22.04
HibernationDevice: RESUME=UUID=88228def-1fb1-4fc3-964c-3106218355eb
InstallationDate: Installed on 2020-08-29 (613 days ago)
InstallationMedia: Ubuntu-MATE 20.04.1 LTS "Focal Fossa" - Release amd64 (20200731)
IwConfig:
 lo no wireless extensions.

 enp7s0 no wireless extensions.

 tun0 no wireless extensions.
MachineType: System manufacturer System Product Name
Package: xorg-server
PackageArchitecture: amd64
ProcFB: 0 radeondrmfb
ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-5.15.0-25-generic root=/dev/mapper/vgubuntu--mate-root ro quiet splash vt.handoff=7
ProcVersionSignature: Ubuntu 5.15.0-25.25-generic 5.15.30
RelatedPackageVersions:
 linux-restricted-modules-5.15.0-25-generic N/A
 linux-backports-modules-5.15.0-25-generic N/A
 linux-firmware 20220329.git681281e4-0ubuntu1
RfKill:

Tags: jammy
Uname: Linux 5.15.0-25-generic x86_64
UpgradeStatus: Upgraded to jammy on 2022-04-21 (13 days ago)
UserGroups: adm cdrom dip lpadmin lxd plugdev sambashare sudo
_MarkForUpload: True
dmi.bios.date: 12/02/2020
dmi.bios.release: 5.17
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: 5809
dmi.board.asset.tag: Default string
dmi.board.name: TUF X470-PLUS GAMING
dmi.board.vendor: ASUSTeK COMPUTER INC.
dmi.board.version: Rev X.0x
dmi.chassis.asset.tag: Default string
dmi.chassis.type: 3
dmi.chassis.vendor: Default string
dmi.chassis.version: Default string
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr5809:bd12/02/2020:br5.17:svnSystemmanufacturer:pnSystemProductName:pvrSystemVersion:rvnASUSTeKCOMPUTERINC.:rnTUFX470-PLUSGAMING:rvrRevX.0x:cvnDefaultstring:ct3:cvrDefaultstring:skuSKU:
dmi.product.family: To be filled by O.E.M.
dmi.product.name: System Product Name
dmi.product.sku: SKU
dmi.product.version: System Version
dmi.sys.vendor: System manufacturer