diff --git a/bidi-test.py b/bidi-test.py
index fed7b20..60dc44e 100755
--- a/bidi-test.py
+++ b/bidi-test.py
@@ -5,6 +5,7 @@ import logging
 import os
 import threading
 import time
+from pathlib import Path
 from typing import Any
 
 import bidi
@@ -58,6 +59,18 @@ class Browser:
 
         asyncio.run_coroutine_threadsafe(self.driver.start_session(), self.loop).result()
 
+        test_functions = Path("test-functions.js").read_text()
+        self.bidi("script.addPreloadScript", functionDeclaration=f"() => {{ {test_functions} }}")
+
+        try:
+            sizzle_js = (Path(__file__).parent / "node_modules/sizzle/dist/sizzle.js").read_text()
+            # HACK: sizzle tracks document and when we switch frames, it sees the old document
+            # although we execute it in different context.
+            sizzle_js = sizzle_js.replace('context = context || document;', 'context = context || window.document;')
+            self.bidi("script.addPreloadScript", functionDeclaration=f"() => {{ {sizzle_js} }}")
+        except FileNotFoundError:
+            pass
+
     def close(self):
         asyncio.run_coroutine_threadsafe(self.driver.close(), self.loop).result()
         self.loop.call_soon_threadsafe(self.loop.stop)
@@ -196,6 +209,7 @@ try:
     b.wait_text("#super-user-indicator", "Limited access")
 
     b.switch_to_frame("cockpit1:localhost/system")
+    b.wait_visible(".pf-v5-c-alert:contains('Web console is running in limited access mode.')")
     b.wait_in_text(".system-configuration", "Join domain")
 
     b.switch_to_top()
diff --git a/bidi.py b/bidi.py
index 3fa5c9e..bf4be8b 100755
--- a/bidi.py
+++ b/bidi.py
@@ -127,9 +127,6 @@ class WebdriverBidi:
             "log.entryAdded", "browsingContext.domContentLoaded",
         ])
 
-        test_functions = Path("test-functions.js").read_text()
-        await self.bidi("script.addPreloadScript", functionDeclaration=f"() => {{ {test_functions} }}")
-
         # wait for browser to initialize default context
         for _ in range(10):
             realms = (await self.bidi("script.getRealms"))["realms"]
@@ -193,7 +190,8 @@ class WebdriverBidi:
         """Send a Webdriver BiDi command and return the JSON response"""
 
         payload = json.dumps({"id": self.last_id, "method": method, "params": params})
-        log_proto.debug("ws ← %r", payload)
+        # avoid log spam for preload scripts
+        log_proto.debug("ws ← %r", method if method == "script.addPreloadScript" else payload)
         await self.ws.send_str(payload)
         future = asyncio.get_event_loop().create_future()
         self.pending_commands[self.last_id] = future
diff --git a/package.json b/package.json
index b08cfd1..996f4ec 100644
--- a/package.json
+++ b/package.json
@@ -42,6 +42,7 @@
     "jed": "1.1.1",
     "qunit": "2.21.1",
     "sass": "1.77.8",
+    "sizzle": "2.3.10",
     "stylelint": "16.7.0",
     "stylelint-config-recommended-scss": "14.0.0",
     "stylelint-config-standard": "36.0.1",
diff --git a/test-functions.js b/test-functions.js
index 633e3fe..9b5b19a 100644
--- a/test-functions.js
+++ b/test-functions.js
@@ -1,8 +1,4 @@
 window.ph_select = function(sel) {
-    if (!window.Sizzle) {
-        return Array.from(document.querySelectorAll(sel));
-    }
-
     if (sel.includes(":contains(")) {
         if (!window.Sizzle) {
             throw new Error("Using ':contains' when window.Sizzle is not available.");