diff --git a/demos/node-editor/node-editor-application.c b/demos/node-editor/node-editor-application.c
index dfcc5b4aa9..5c0ff7bf83 100644
--- a/demos/node-editor/node-editor-application.c
+++ b/demos/node-editor/node-editor-application.c
@@ -299,7 +299,7 @@ node_editor_application_new (void)
 
   app = g_object_new (NODE_EDITOR_APPLICATION_TYPE,
                       "application-id", "org.gtk.gtk4.NodeEditor",
-                      "flags", G_APPLICATION_HANDLES_OPEN,
+                      "flags", G_APPLICATION_HANDLES_OPEN | G_APPLICATION_NON_UNIQUE,
                       NULL);
 
   g_application_add_main_option (G_APPLICATION (app), "version", 0, 0,G_OPTION_ARG_NONE, "Show program version", NULL);
diff --git a/gsk/gpu/gskvulkanimage.c b/gsk/gpu/gskvulkanimage.c
index d987dbad6f..5b5228d06a 100644
--- a/gsk/gpu/gskvulkanimage.c
+++ b/gsk/gpu/gskvulkanimage.c
@@ -202,6 +202,9 @@ gsk_vulkan_device_check_format (GskVulkanDevice          *device,
 #define CHECK_FLAGS (GSK_GPU_IMAGE_NO_BLIT | GSK_GPU_IMAGE_FILTERABLE | GSK_GPU_IMAGE_RENDERABLE)
   GskGpuImageFlags flags;
 
+  if (vk_format == VK_FORMAT_UNDEFINED)
+    return FALSE;
+
   if (vk_usage & VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT &&
       !gsk_component_mapping_is_framebuffer_compatible (vk_components))
     return FALSE;
@@ -261,15 +264,13 @@ gsk_vulkan_image_new (GskVulkanDevice           *device,
 
   /* First, try the actual format */
   vk_format = gdk_memory_format_vk_format (format, &vk_components);
-  if (vk_format == VK_FORMAT_UNDEFINED ||
-      !gsk_vulkan_device_check_format (device, vk_format, &vk_components, required_flags,
+  if (!gsk_vulkan_device_check_format (device, vk_format, &vk_components, required_flags,
                                        tiling, usage, width, height,
                                        &tiling, &flags))
     {
       /* Second, try the potential RGBA format */
       vk_format = gdk_memory_format_vk_rgba_format (format, NULL, &vk_components);
-      if (vk_format == VK_FORMAT_UNDEFINED ||
-          !gsk_vulkan_device_check_format (device, vk_format, &vk_components, required_flags,
+      if (!gsk_vulkan_device_check_format (device, vk_format, &vk_components, required_flags,
                                            tiling, usage, width, height,
                                            &tiling, &flags))
         {
@@ -281,8 +282,7 @@ gsk_vulkan_image_new (GskVulkanDevice           *device,
           for (i = 0; fallbacks[i] != -1; i++)
             {
               vk_format = gdk_memory_format_vk_format (fallbacks[i], &vk_components);
-              if (vk_format != VK_FORMAT_UNDEFINED &&
-                  gsk_vulkan_device_check_format (device, vk_format, &vk_components, required_flags,
+              if (gsk_vulkan_device_check_format (device, vk_format, &vk_components, required_flags,
                                                   tiling, usage, width, height,
                                                   &tiling, &flags))
                 {
diff --git a/testsuite/gdk/memorytexture.c b/testsuite/gdk/memorytexture.c
index 51b85cd0e4..4aca11c32f 100644
--- a/testsuite/gdk/memorytexture.c
+++ b/testsuite/gdk/memorytexture.c
@@ -835,7 +835,22 @@ compare_textures (GdkTexture *texture1,
     {
       for (x = 0; x < width; x++)
         {
-          g_assert_true (gdk_memory_format_pixel_equal (format, accurate_compare, data1 + bpp * x, data2 + bpp * x));
+          if (!gdk_memory_format_pixel_equal (format, accurate_compare, data1 + bpp * x, data2 + bpp * x))
+            {
+              gsize i;
+              GString *msg = g_string_new (NULL);
+
+              g_string_append_printf (msg, "(%u %u): ", x, y);
+              for (i = 0; i < bpp; i++)
+                g_string_append_printf (msg, "%02X", data1[bpp * x + i]);
+              g_string_append (msg, " != ");
+              for (i = 0; i < bpp; i++)
+                g_string_append_printf (msg, "%02X", data2[bpp * x + i]);
+
+              g_test_message ("%s", msg->str);
+              g_string_free (msg, TRUE);
+              g_test_fail ();
+            }
         }
       data1 += stride1;
       data2 += stride2;