diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 37a58f48bb..ed614bcdc5 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -77,7 +77,8 @@ jobs:
             doxygen \
             python3-docutils \
             python3-lxml \
-            rst2pdf
+            rst2pdf \
+            xvfb
 
       - name: Configure
         run: |
@@ -94,12 +95,12 @@ jobs:
       - name: Run Tests
         run: |
           cd _build
-          make -j ${{ env.JOBS }} check
+          xvfb-run -a -e /tmp/xvfb-error-make-tests make -j ${{ env.JOBS }} check
 
       - name: Run distcheck
         run: |
           cd _build
-          make -j ${{ env.JOBS }} distcheck DISTCHECK_CONFIGURE_FLAGS="$CONFIGURE_FLAGS";
+          xvfb-run -a -e /tmp/xvfb-error-make-distcheck make -j ${{ env.JOBS }} distcheck DISTCHECK_CONFIGURE_FLAGS="$CONFIGURE_FLAGS";
 
       - name: ccache statistics
         run: ccache --show-stats
@@ -150,7 +151,8 @@ jobs:
             python3-docutils \
             python3-lxml \
             rst2pdf \
-            meson
+            meson \
+            xvfb
 
       - name: Configuration
         run: |
@@ -162,7 +164,7 @@ jobs:
 
       - name: Run Tests
         run: |
-          ninja -C _build test
+          xvfb-run -a -e /tmp/xvfb-error-meson-tests ninja -C _build test
 
       # distcheck not applicable, meson exports the source tree per git-archive
 
diff --git a/tests/test_sidebar.c b/tests/test_sidebar.c
index 9659dc72e7..c03d1aa649 100644
--- a/tests/test_sidebar.c
+++ b/tests/test_sidebar.c
@@ -137,12 +137,21 @@ void test_sidebar_openfiles_tree(void)
 
 int main(int argc, char **argv)
 {
-	g_test_init(&argc, &argv, NULL);
-	/* Not sure if we can really continue without DISPLAY. Fake X display perhaps?
+	/* In headless environments that do not provide a virtual display,
+	 * GTK initialisation is expected to fail and gtk_init_check()
+	 * will return FALSE. Calling any GTK function or instantiating
+	 * any GTK type afterwards results in undefined behavior.
 	 *
-	 * This test seems to work, at least.
+	 * By returning 77, we can tell test harnesses compatible with
+	 * the GNU standard approach to regard the test as skipped.
 	 */
-	gtk_init_check(&argc, &argv);
+	if (! gtk_init_check(&argc, &argv))
+	{
+		g_test_message("GTK initialization failed; skipping. Running inside a headless environment?");
+		return 77;
+	}
+
+	g_test_init(&argc, &argv, NULL);
 
 	main_init_headless();