[tests:fix] Addressed Selenium unsaved changes test #902

Chromium v126 auto-accepts beforeunload dialogs in classic WebDriver
sessions, causing Selenium tests waiting for alerts to fail.

This change updates the test strategy to reliably detect unsaved
changes without relying on deprecated beforeunload alert behavior.

Fixes #902

Co-authored-by: Federico Capoano <f.capoano@openwisp.io>

Author: Mahathi-s154

openwisp_controller/config/tests/test_selenium.py

@@ -1,12 +1,15 @@
+import os
 import time
 
 from django.contrib.staticfiles.testing import StaticLiveServerTestCase
 from django.test import tag
 from django.urls.base import reverse
+from selenium import webdriver
 from selenium.common.exceptions import TimeoutException
 from selenium.webdriver.common.action_chains import ActionChains
 from selenium.webdriver.common.by import By
 from selenium.webdriver.common.keys import Keys
+from selenium.webdriver.common.utils import free_port
 from selenium.webdriver.support import expected_conditions as EC
 from selenium.webdriver.support.ui import Select, WebDriverWait
 from swapper import load_model
@@ -498,6 +501,37 @@ class TestDeviceAdminUnsavedChanges(
 ):
     browser = "chrome"
 
+    @classmethod
+    def get_chrome_webdriver(cls):
+        """
+        Override the parent class method to enable BiDi mode and set
+        unhandledPromptBehavior to "ignore". This is required to test
+        beforeunload alerts, as Chromium v126+ auto-accepts them per
+        WebDriver standard.
+
+        Ref: https://github.com/openwisp/openwisp-controller/issues/902
+        """
+        options = webdriver.ChromeOptions()
+        options.page_load_strategy = "eager"
+        if os.environ.get("SELENIUM_HEADLESS", False):
+            options.add_argument("--headless")
+        CHROME_BIN = os.environ.get("CHROME_BIN", None)
+        if CHROME_BIN:
+            options.binary_location = CHROME_BIN
+        options.add_argument("--window-size=1366,768")
+        options.add_argument("--ignore-certificate-errors")
+        options.add_argument("--no-sandbox")
+        options.add_argument("--disable-gpu")
+        options.add_argument("--disable-dev-shm-usage")
+        options.add_argument("--disable-features=VizDisplayCompositor")
+        options.add_argument(f"--remote-debugging-port={free_port()}")
+        options.set_capability("goog:loggingPrefs", {"browser": "ALL"})
+        # Enable BiDi mode and set unhandledPromptBehavior to "ignore"
+        # to allow testing beforeunload alerts (Chromium v126+).
+        options.enable_bidi = True
+        options.set_capability("unhandledPromptBehavior", "ignore")
+        return webdriver.Chrome(options=options)
+
     def _is_unsaved_changes_alert_present(self):
         for entry in self.get_browser_logs():
             if (