Firefox configuration in Selenium Python - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a Firefox WebDriver instance.

Selenium Python

from selenium import webdriver

browser = webdriver.Firefox([1])

Drag options to blanks, or click blank then click option'

Aexecutable_path='geckodriver.exe'

Boptions=None

Cservice=None

Dfirefox_profile=None

Attempts:

3 left

💡 Hint

Common Mistakes

Using deprecated 'executable_path' parameter.

Passing 'options' without creating FirefoxOptions object.

The service parameter is used to specify the geckodriver executable service in Selenium 4+. Passing service=None uses the default service.

2fill in blank

medium

Complete the code to set Firefox to run in headless mode.

Selenium Python

from selenium.webdriver.firefox.options import Options

options = Options()
options.[1] = True

browser = webdriver.Firefox(options=options)

Drag options to blanks, or click blank then click option'

Aheadless

Bset_headless

Cenable_headless

Drun_headless

Attempts:

3 left

💡 Hint

Common Mistakes

Using a method name instead of a property.

Misspelling the property name.

Setting options.headless = True enables headless mode in Firefox.

3fill in blank

hard

Fix the error in the code to set a custom Firefox profile path.

Selenium Python

from selenium.webdriver.firefox.firefox_profile import FirefoxProfile

profile = FirefoxProfile('[1]')
browser = webdriver.Firefox(firefox_profile=profile)

Drag options to blanks, or click blank then click option'

AC:\Users\User\AppData\Roaming\Mozilla\Firefox\Profiles\xyz.default

Bcustom/profile/path

Cprofile/path

D/path/to/custom/profile

Attempts:

3 left

💡 Hint

Common Mistakes

Using relative or incomplete paths.

Using single backslashes without escaping on Windows.

The FirefoxProfile constructor requires the full absolute path to the profile folder. The Windows path with double backslashes is correct.

4fill in blank

hard

Fill both blanks to set a Firefox preference and start the browser with it.

Selenium Python

from selenium.webdriver.firefox.options import Options
from selenium.webdriver.firefox.firefox_profile import FirefoxProfile

profile = FirefoxProfile()
profile.set_preference('[1]', [2])

browser = webdriver.Firefox(firefox_profile=profile)

Drag options to blanks, or click blank then click option'

Ajavascript.enabled

Bnetwork.proxy.type

CTrue

D0

Attempts:

3 left

💡 Hint

Common Mistakes

Using incorrect preference names.

Passing string 'True' instead of boolean True.

Setting javascript.enabled to True enables JavaScript in Firefox.

5fill in blank

hard

Fill all three blanks to create a Firefox WebDriver with headless mode and a custom profile path.

Selenium Python

from selenium import webdriver
from selenium.webdriver.firefox.options import Options
from selenium.webdriver.firefox.firefox_profile import FirefoxProfile

options = Options()
options.[1] = True
profile = FirefoxProfile('[2]')
browser = webdriver.Firefox(options=options, firefox_profile=profile, service=[3])

Drag options to blanks, or click blank then click option'

Aheadless

BC:\Users\User\AppData\Roaming\Mozilla\Firefox\Profiles\xyz.default

CNone

DTrue

Attempts:

3 left

💡 Hint

Common Mistakes

Using incorrect property names for headless mode.

Using relative or incomplete profile paths.

Passing incorrect service parameter values.

Set options.headless = True to run Firefox headless, provide the full profile path, and pass service=None to use default driver service.

Practice

1. What is the main purpose of using FirefoxOptions() in Selenium tests?

easy

A. To configure Firefox browser settings before starting the test

B. To write test assertions for Firefox browser

C. To locate elements on a Firefox webpage

D. To generate test reports for Firefox tests

Solution

1. Step 1: Understand the role of FirefoxOptions

   FirefoxOptions() is used to set browser preferences like headless mode or disable notifications before launching Firefox.

2. Step 2: Differentiate from other Selenium tasks

   Locating elements, assertions, and reports are separate tasks not handled by FirefoxOptions().

3. Final Answer:

   To configure Firefox browser settings before starting the test -> Option A

4. Quick Check:

   FirefoxOptions() = configure browser [OK]

Hint: Options set browser behavior before test starts [OK]

Common Mistakes:

• Confusing options with element locators
• Thinking options generate reports
• Mixing options with assertions

2. Which of the following is the correct way to enable headless mode in Firefox using Selenium Python?

easy

A. options = FirefoxOptions()
options.set_headless(True)

B. options = FirefoxOptions()
options.add_argument('--headless')

C. options = FirefoxOptions()
options.headless = True

D. options = FirefoxOptions()
options.enable_headless()

Solution

1. Step 1: Recall correct syntax for headless mode

   In Selenium Python, options.headless = True is the standard way to enable headless mode for Firefox.

2. Step 2: Check other options for correctness

   set_headless() and enable_headless() are not valid methods. add_argument('--headless') works for Chrome but not recommended for Firefox.

3. Final Answer:

   options = FirefoxOptions() options.headless = True -> Option C

4. Quick Check:

   Set options.headless = True for Firefox headless [OK]

Hint: Use options.headless = True for Firefox headless mode [OK]

Common Mistakes:

• Using Chrome syntax like add_argument('--headless')
• Calling non-existent methods like set_headless()
• Forgetting to create FirefoxOptions instance

3. What will be the output of the following code snippet?

from selenium.webdriver import Firefox
from selenium.webdriver.firefox.options import Options

options = Options()
options.headless = True
browser = Firefox(options=options)
print(browser.capabilities['moz:headless'])
browser.quit()

medium

A. KeyError exception

B. True

C. None

D. False

Solution

1. Step 1: Understand headless option effect on capabilities

   Setting options.headless = True tells Firefox to run without UI, reflected in capabilities under key 'moz:headless' as True.

2. Step 2: Check the print statement output

   The print statement accesses browser.capabilities['moz:headless'], which will be True because headless mode is enabled.

3. Final Answer:

   True -> Option B

4. Quick Check:

   Headless mode enabled means moz:headless = True [OK]

Hint: Check capabilities key 'moz:headless' for headless status [OK]

Common Mistakes:

• Assuming 'moz:headless' key is missing
• Expecting False when headless is set True
• Confusing capabilities with options

4. Identify the error in the following Firefox configuration code and select the fix:

from selenium.webdriver import Firefox
from selenium.webdriver.firefox.options import Options

options = Options()
options.headless(True)
browser = Firefox(options=options)
browser.quit()

medium

A. Change options.headless(True) to options.headless = True

B. Import FirefoxOptions instead of Options

C. Add browser.quit() before creating browser

D. Remove options argument from Firefox() constructor

Solution

1. Step 1: Identify incorrect method call

   The line options.headless(True) incorrectly calls headless as a method, but it is a property to set.

2. Step 2: Correct syntax for setting headless

   It should be options.headless = True to enable headless mode properly.

3. Final Answer:

   Change options.headless(True) to options.headless = True -> Option A

4. Quick Check:

   Set headless as property, not method [OK]

Hint: Use assignment (=), not function call, for headless [OK]

Common Mistakes:

• Calling headless as a method
• Confusing Options class import
• Misplacing browser.quit() call

5. You want to disable Firefox notifications during Selenium tests to avoid pop-ups. Which code snippet correctly sets this preference using FirefoxOptions?

hard

A. options = FirefoxOptions()
options.set_capability('notifications', False)

B. options = FirefoxOptions()
options.add_argument('--disable-notifications')

C. options = FirefoxOptions()
options.headless = False
options.disable_notifications = True

D. options = FirefoxOptions()
options.set_preference('dom.webnotifications.enabled', False)

Solution

1. Step 1: Identify correct method to set Firefox preferences

   Use options.set_preference() to set Firefox-specific preferences like disabling notifications.

2. Step 2: Verify preference key and value

   The key 'dom.webnotifications.enabled' controls notifications; setting it to False disables them.

3. Final Answer:

   options = FirefoxOptions() options.set_preference('dom.webnotifications.enabled', False) -> Option D

4. Quick Check:

   Use set_preference with correct key to disable notifications [OK]

Hint: Use set_preference('dom.webnotifications.enabled', False) [OK]

Common Mistakes:

• Using add_argument for Firefox preferences
• Setting non-existent properties like disable_notifications
• Confusing capabilities with preferences