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--- linux:apps:kvm:client-resolution [2026/09/03 19:42] – oscar
+++ linux:apps:kvm:client-resolution [2026/09/13 06:23] (current) – [Step 2: Fix LightDM Login Screen Resolution] oscar
@@ Line 21: / Line 21: @@
 # nano /etc/lightdm/lightdm.conf
 </code>
-Scroll down or search (Ctrl + W) for the **[Seat:*]** section. Look for the **display-setup-script** line. Uncomment it (remove the #) and add your targeted xrandr command. For example, to force a 1920x1080 resolution:
+Scroll down or search (Ctrl + W) for the **\[Seat:\*\]** section.
+Look for the **display-setup-script** line. Uncomment it (remove the #) and add your targeted xrandr command. For example, to force a 1920x1080 resolution:
 <code>
 ...
@@ Line 32: / Line 33: @@
 ===== Step 3: Optimize Virt-Manager Hardware Settings =====
-(If still limited)If you cannot select higher resolutions inside XFCE's Settings > Display, you may need to adjust the virtual hardware layout
+(If still limited)If you cannot select higher resolutions inside XFCE's Settings > Display, you may need to adjust the virtual hardware layout:
+  - Shut down the virtual machine.
+  - Open the VM's hardware details window (the Lightbulb icon in virt-manager).
+  - Select the Video device:
+    - Recommended Layout: Set the model to Virtio (with 3D Acceleration disabled if XFCE experiences black screen bugs) or QXL.
+    - RAM Allocation: If using higher resolutions (like 1440p or 4K), increase the Video RAM or vgamem value from 16MB to 64MB or 128MB to ensure the virtual framebuffer can support the pixel density.
+  - Make sure your Display device is set to Spice server.
+  - Boot the VM
+===== Step 4: Fallback Script for Sticky XFCE Resizing =====
+If XFCE forgets your resolution on reboot despite spice-vdagent running, you can force it into your user profile via XFCE Autostart:
+  * Open Applications Menu > Settings > Session and Startup.
+  * Go to the Application Autostart tab.
+  * Click the + Add button.
+  * Fill in the prompt:
+  * Name: Force Resolution
+  * Command: xrandr --output Virtual-1 --mode 1920x1080 (adjust to match your setup)
+  * Click OK.
+With these configurations in place, LightDM will scale elegantly on startup, and your XFCE desktop will automatically expand to match your host monitor.
+If your screen stays black or fails to register changes, let me know your Linux host/guest distribution and the exact Video model type you selected in virt-manager!