From: PT Linux Launcher maintainers
Subject: Use a backing surface for letter-boxing

Backport upstream commit 66450376038864700f9b4721343b4d15b29c4198 so
native Wayland presentation covers the complete configured output when the
game layer is unity-scaled with a non-zero letterbox offset.

--- a/src/Backends/WaylandBackend.cpp
+++ b/src/Backends/WaylandBackend.cpp
@@ -1081,7 +1081,10 @@ namespace gamescope
                 bool bNeedsBacking = true;
                 if ( pFrameInfo->layerCount >= 1 )
                 {
-                    if ( pFrameInfo->layers[0].isScreenSize() && !pFrameInfo->layers[0].hasAlpha() )
+                    if ( pFrameInfo->layers[0].isScreenSize() &&
+                         close_enough( pFrameInfo->layers[0].offset.x, 0.0f ) &&
+                         close_enough( pFrameInfo->layers[0].offset.y, 0.0f ) &&
+                         !pFrameInfo->layers[0].hasAlpha() )
                         bNeedsBacking = false;
                 }