diff --git a/backend/app/services/document_conversion/html_to_pdf.py b/backend/app/services/document_conversion/html_to_pdf.py
index c1b9b8d78..ca8c5edac 100644
--- a/backend/app/services/document_conversion/html_to_pdf.py
+++ b/backend/app/services/document_conversion/html_to_pdf.py
@@ -35,19 +35,25 @@ async def try_chrome_pdf() -> bool:
                 port = sock.getsockname()[1]
 
             profile_dir = tempfile.TemporaryDirectory(prefix="clawith-html-pdf-")
+            chrome_args = [
+                chrome,
+                "--headless=new",
+                "--disable-gpu",
+                "--disable-dev-shm-usage",
+                "--no-first-run",
+                "--no-default-browser-check",
+                "--allow-file-access-from-files",
+                f"--remote-debugging-port={port}",
+                f"--user-data-dir={profile_dir.name}",
+                "about:blank",
+            ]
+            import sys
+            if sys.platform.startswith("linux"):
+                # Linux environments (like Docker containers) require no-sandbox in standard restricted container contexts
+                chrome_args.extend(["--no-sandbox", "--disable-setuid-sandbox"])
+
             proc = subprocess.Popen(
-                [
-                    chrome,
-                    "--headless=new",
-                    "--disable-gpu",
-                    "--disable-dev-shm-usage",
-                    "--no-first-run",
-                    "--no-default-browser-check",
-                    "--allow-file-access-from-files",
-                    f"--remote-debugging-port={port}",
-                    f"--user-data-dir={profile_dir.name}",
-                    "about:blank",
-                ],
+                chrome_args,
                 stdout=subprocess.DEVNULL,
                 stderr=subprocess.DEVNULL,
             )
@@ -152,8 +158,12 @@ async def send(method: str, params: dict[str, Any] | None = None) -> dict[str, A
                 profile_dir.cleanup()
 
         try:
-            if await try_chrome_pdf():
+            chrome_success = await try_chrome_pdf()
+            if chrome_success:
                 return f"✅ Successfully converted HTML to PDF with Chrome: {target_path}"
+            else:
+                chrome_pdf_error = Exception("Chrome process timed out or failed to connect to debugging port")
+                logger.warning("Chrome HTML to PDF failed (timed out), falling back to WeasyPrint")
         except Exception as exc:
             chrome_pdf_error = exc
             logger.warning(f"Chrome HTML to PDF failed, falling back to WeasyPrint: {exc}")
diff --git a/backend/tests/test_html_to_pdf.py b/backend/tests/test_html_to_pdf.py
new file mode 100644
index 000000000..a791466cb
--- /dev/null
+++ b/backend/tests/test_html_to_pdf.py
@@ -0,0 +1,64 @@
+import sys
+import pytest
+from unittest.mock import MagicMock, patch
+from pathlib import Path
+from app.services.document_conversion.html_to_pdf import convert_html_to_pdf
+
+@pytest.mark.asyncio
+@patch("app.services.document_conversion.html_to_pdf.chrome_executable")
+@patch("subprocess.Popen")
+@patch("time.time")
+@patch("weasyprint.HTML")
+async def test_convert_html_to_pdf_linux(mock_weasy_html, mock_time, mock_popen, mock_chrome_exec):
+    mock_chrome_exec.return_value = "/usr/bin/google-chrome"
+    mock_time.side_effect = [1000.0, 1010.0]  # Fails deadline immediately
+    
+    # Mock subprocess.Popen
+    mock_proc = MagicMock()
+    mock_popen.return_value = mock_proc
+    
+    # Mock weasyprint HTML write_pdf
+    mock_weasy_instance = MagicMock()
+    mock_weasy_html.return_value = mock_weasy_instance
+
+    src = Path("/tmp/src.html")
+    tgt = Path("/tmp/tgt.pdf")
+    
+    with patch("sys.platform", "linux"):
+        res = await convert_html_to_pdf(src, tgt, "tgt.pdf", {})
+        
+    assert mock_popen.called
+    args = mock_popen.call_args[0][0]
+    assert "--no-sandbox" in args
+    assert "--disable-setuid-sandbox" in args
+    assert "WeasyPrint" in res
+
+
+@pytest.mark.asyncio
+@patch("app.services.document_conversion.html_to_pdf.chrome_executable")
+@patch("subprocess.Popen")
+@patch("time.time")
+@patch("weasyprint.HTML")
+async def test_convert_html_to_pdf_darwin(mock_weasy_html, mock_time, mock_popen, mock_chrome_exec):
+    mock_chrome_exec.return_value = "/usr/bin/google-chrome"
+    mock_time.side_effect = [1000.0, 1010.0]  # Fails deadline immediately
+    
+    # Mock subprocess.Popen
+    mock_proc = MagicMock()
+    mock_popen.return_value = mock_proc
+    
+    # Mock weasyprint HTML write_pdf
+    mock_weasy_instance = MagicMock()
+    mock_weasy_html.return_value = mock_weasy_instance
+
+    src = Path("/tmp/src.html")
+    tgt = Path("/tmp/tgt.pdf")
+    
+    with patch("sys.platform", "darwin"):
+        res = await convert_html_to_pdf(src, tgt, "tgt.pdf", {})
+        
+    assert mock_popen.called
+    args = mock_popen.call_args[0][0]
+    assert "--no-sandbox" not in args
+    assert "--disable-setuid-sandbox" not in args
+    assert "WeasyPrint" in res