diff --git a/libs/filamentapp/src/FilamentApp.cpp b/libs/filamentapp/src/FilamentApp.cpp
index 2521bf6a27..98760003d5 100644
--- a/libs/filamentapp/src/FilamentApp.cpp
+++ b/libs/filamentapp/src/FilamentApp.cpp
@@ -323,13 +323,17 @@ void FilamentApp::run(const Config& config, SetupCallback setupCallback,
         if (mImGuiHelper) {
 
             // Inform ImGui of the current window size in case it was resized.
-            int windowWidth, windowHeight;
-            int displayWidth, displayHeight;
-            SDL_GetWindowSize(window->mWindow, &windowWidth, &windowHeight);
-            SDL_GL_GetDrawableSize(window->mWindow, &displayWidth, &displayHeight);
-            mImGuiHelper->setDisplaySize(windowWidth, windowHeight,
-                    windowWidth > 0 ? ((float)displayWidth / windowWidth) : 0,
-                    displayHeight > 0 ? ((float)displayHeight / windowHeight) : 0);
+            if (config.headless) {
+                mImGuiHelper->setDisplaySize(window->mWidth, window->mHeight);
+            } else {
+                int windowWidth, windowHeight;
+                int displayWidth, displayHeight;
+                SDL_GetWindowSize(window->mWindow, &windowWidth, &windowHeight);
+                SDL_GL_GetDrawableSize(window->mWindow, &displayWidth, &displayHeight);
+                mImGuiHelper->setDisplaySize(windowWidth, windowHeight,
+                        windowWidth > 0 ? ((float)displayWidth / windowWidth) : 0,
+                        displayHeight > 0 ? ((float)displayHeight / windowHeight) : 0);
+            }
 
             // Setup mouse inputs (we already got mouse wheel, keyboard keys & characters
             // from our event handler)
diff --git a/libs/viewer/include/viewer/AutomationEngine.h b/libs/viewer/include/viewer/AutomationEngine.h
index 3f578aa02b..a3ed876ad9 100644
--- a/libs/viewer/include/viewer/AutomationEngine.h
+++ b/libs/viewer/include/viewer/AutomationEngine.h
@@ -88,6 +88,9 @@ public:
         // Similar to sleepDuration, but expressed as a frame count. Both the minimum sleep time
         // and the minimum frame count must be elapsed before the engine advances to the next test.
         int minFrameCount = 2;
+
+        // If true, test progress is dumped to the utils Log (info priority).
+        bool verbose = true;
     };
 
     Options getOptions() const { return mOptions; }
diff --git a/libs/viewer/src/AutomationEngine.cpp b/libs/viewer/src/AutomationEngine.cpp
index 17a0c98bfc..2bc7dcc1c1 100644
--- a/libs/viewer/src/AutomationEngine.cpp
+++ b/libs/viewer/src/AutomationEngine.cpp
@@ -25,6 +25,7 @@
 
 #include <backend/PixelBufferDescriptor.h>
 
+#include <utils/Log.h>
 #include <utils/Path.h>
 
 #include <iomanip>
@@ -133,6 +134,9 @@ void AutomationEngine::tick(View* view, MaterialInstance* const* materials, size
         for (size_t i = 0; i < materialCount; i++) {
             applySettings(mSettings->material, materials[i]);
         }
+        if (mOptions.verbose) {
+            utils::slog.i << "Running test " << mCurrentTest << utils::io::endl;
+        }
     };
 
     if (!mIsRunning) {
diff --git a/samples/gltf_viewer.cpp b/samples/gltf_viewer.cpp
index d6a87927ef..b1c22042da 100644
--- a/samples/gltf_viewer.cpp
+++ b/samples/gltf_viewer.cpp
@@ -134,6 +134,8 @@ static void printUsage(char* name) {
         "       Specify the backend API: opengl (default), vulkan, or metal\n\n"
         "   --batch=<path to JSON file or 'default'>, -b\n"
         "       Start automation using the given JSON spec, then quit the app\n\n"
+        "   --headless, -e\n"
+        "       Use a headless swapchain; ignored if --batch is not present\n\n"
         "   --ibl=<path to cmgen IBL>, -i <path>\n"
         "       Override the built-in IBL\n\n"
         "   --actual-size, -s\n"
@@ -166,11 +168,12 @@ static std::ifstream::pos_type getFileSize(const char* filename) {
 }
 
 static int handleCommandLineArguments(int argc, char* argv[], App* app) {
-    static constexpr const char* OPTSTR = "ha:i:usc:rt:b:";
+    static constexpr const char* OPTSTR = "ha:i:usc:rt:b:e";
     static const struct option OPTIONS[] = {
         { "help",         no_argument,       nullptr, 'h' },
         { "api",          required_argument, nullptr, 'a' },
         { "batch",        required_argument, nullptr, 'b' },
+        { "headless",     no_argument,       nullptr, 'e' },
         { "ibl",          required_argument, nullptr, 'i' },
         { "ubershader",   no_argument,       nullptr, 'u' },
         { "actual-size",  no_argument,       nullptr, 's' },
@@ -208,6 +211,9 @@ static int handleCommandLineArguments(int argc, char* argv[], App* app) {
                     std::cerr << "Unrecognized camera mode. Must be 'flight'|'orbit'.\n";
                 }
                 break;
+            case 'e':
+                app->config.headless = true;
+                break;
             case 'i':
                 app->config.iblDirectory = arg;
                 break;
@@ -229,6 +235,10 @@ static int handleCommandLineArguments(int argc, char* argv[], App* app) {
             }
         }
     }
+    if (app->config.headless && app->batchFile.empty()) {
+        std::cerr << "--headless is allowed only when --batch is present." << std::endl;
+        app->config.headless = false;
+    }
     return optind;
 }