Browser profile configuration in Selenium Python - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a Firefox profile object.

Selenium Python

from selenium.webdriver import FirefoxProfile
profile = [1]()

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

AFirefoxProfile

BFirefoxOptions

CWebDriver

DService

Attempts:

3 left

💡 Hint

Common Mistakes

Using FirefoxOptions() instead of FirefoxProfile()

Trying to create a profile with WebDriver class

Using Service class which is for driver service setup

The FirefoxProfile() creates a new Firefox profile object to customize browser settings.

2fill in blank

medium

Complete the code to set a preference in the Firefox profile.

Selenium Python

profile = FirefoxProfile()
profile.[1]('browser.startup.homepage', 'https://example.com')

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

Aset_option

Badd_argument

Cadd_preference

Dset_preference

Attempts:

3 left

💡 Hint

Common Mistakes

Using add_argument which is for command line options

Using set_option which is not a Firefox profile method

Using add_preference which does not exist

The method set_preference is used to set Firefox profile preferences like homepage URL.

3fill in blank

hard

Fix the error in the code to load the Firefox profile into options.

Selenium Python

from selenium.webdriver import Firefox, FirefoxOptions, FirefoxProfile
profile = FirefoxProfile()
options = FirefoxOptions()
options.[1] = profile.path
browser = Firefox(options=options)

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

Aprofile

Badd_profile

Cprofile_path

Dset_profile

Attempts:

3 left

💡 Hint

Common Mistakes

Forgetting .path: options.profile = profile

Using profile_path which is not an attribute

Using add_profile which does not exist

The correct way to assign a profile to options is options.profile = profile.path.

4fill in blank

hard

Fill both blanks to create a Firefox driver with a custom profile and disable notifications.

Selenium Python

profile = FirefoxProfile()
profile.[1]('dom.webnotifications.enabled', False)
options = FirefoxOptions()
options.[2] = profile.path
driver = Firefox(options=options)

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

Aset_preference

Bprofile

Cadd_argument

Dadd_extension

Attempts:

3 left

💡 Hint

Common Mistakes

Using add_argument instead of set_preference

Forgetting .path or wrong assignment for profile

Using add_extension which is unrelated here

Use set_preference to disable notifications and options.profile = profile.path to assign the profile to options.

5fill in blank

hard

Fill all three blanks to create a Firefox profile, set homepage, assign profile to options, and start the browser.

Selenium Python

profile = FirefoxProfile()
profile.[1]('browser.startup.homepage', 'https://openai.com')
options = FirefoxOptions()
options.[2] = profile.path
driver = Firefox([3]=options)

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

Aset_preference

Bset_profile

Coptions

Dprofile

Attempts:

3 left

💡 Hint

Common Mistakes

Passing profile instead of options to Firefox constructor

Using wrong argument name like profile instead of options

Not setting preference correctly

Set the homepage with set_preference, assign profile with options.profile = profile.path, and pass options as options argument to Firefox.

Practice

1. What is the main purpose of configuring a browser profile in Selenium tests?

easy

A. To write test cases faster

B. To customize browser settings before running tests

C. To increase the speed of Selenium WebDriver

D. To change the programming language of the test

Solution

1. Step 1: Understand browser profile role

   A browser profile allows setting preferences like homepage, notifications, or extensions before tests run.

2. Step 2: Identify the main purpose

   This customization helps simulate different user environments during testing.

3. Final Answer:

   To customize browser settings before running tests -> Option B

4. Quick Check:

   Browser profile = Customize settings [OK]

Hint: Browser profile changes browser setup before tests [OK]

Common Mistakes:

• Thinking it speeds up test execution
• Confusing profile with test case writing
• Believing it changes test language

2. Which of the following is the correct way to set a Firefox browser preference for disabling notifications using Selenium in Python?

easy

A. profile.set_preference('dom.webnotifications.enabled', False)

B. profile.setPreference('dom.webnotifications.enabled', 'false')

C. profile.set_preference('dom.webnotifications.enabled', 'False')

D. profile.set_preference('dom.webnotifications.enabled', 0)

Solution

1. Step 1: Check method name and argument types

   The correct method is set_preference with lowercase 'p' and boolean False (not string).

2. Step 2: Validate option values

   profile.set_preference('dom.webnotifications.enabled', False) uses correct method and boolean False, which disables notifications properly.

3. Final Answer:

   profile.set_preference('dom.webnotifications.enabled', False) -> Option A

4. Quick Check:

   Correct method + boolean False = profile.set_preference('dom.webnotifications.enabled', False) [OK]

Hint: Use set_preference with exact method name and boolean values [OK]

Common Mistakes:

• Using wrong method name like setPreference
• Passing boolean as string 'False'
• Using integer 0 instead of boolean False

3. Consider this Python code snippet configuring a Firefox profile:

from selenium.webdriver.firefox.firefox_profile import FirefoxProfile
profile = FirefoxProfile()
profile.set_preference('browser.startup.homepage', 'https://example.com')
profile.set_preference('dom.webnotifications.enabled', False)
profile.update_preferences()

print(profile.default_preferences['browser.startup.homepage'])

What will be printed when this code runs?

medium

A. https://example.com

B. None

C. KeyError

D. about:blank

Solution

1. Step 1: Understand FirefoxProfile attributes

   The default_preferences attribute is internal and not updated by set_preference. It may not contain the key.

2. Step 2: Predict print behavior

   Accessing profile.default_preferences['browser.startup.homepage'] will raise a KeyError because this key is not in default_preferences.

3. Final Answer:

   KeyError -> Option C

4. Quick Check:

   Accessing missing key = KeyError [OK]

Hint: Access only updated prefs, not default_preferences dict [OK]

Common Mistakes:

• Assuming set_preference updates default_preferences
• Expecting print to show new homepage URL
• Ignoring that KeyError occurs on missing dict key

4. You wrote this code to disable Firefox notifications but it still shows notifications during tests:

profile = FirefoxProfile()
profile.set_preference('dom.webnotifications.enabled', 'false')
profile.update_preferences()

What is the likely cause of this problem?

medium

A. The method update_preferences() is deprecated and should be removed

B. Missing call to profile.save() before using profile

C. Notifications cannot be disabled via profile settings

D. The preference value should be boolean False, not string 'false'

Solution

1. Step 1: Check preference value type

   The value 'false' is a string, but the preference expects a boolean False to disable notifications.

2. Step 2: Understand effect of wrong type

   Passing string 'false' does not disable notifications, so they still appear.

3. Final Answer:

   The preference value should be boolean False, not string 'false' -> Option D

4. Quick Check:

   Boolean False needed, not string 'false' [OK]

Hint: Use boolean False, not string, to disable prefs [OK]

Common Mistakes:

• Using string 'false' instead of boolean False
• Thinking update_preferences() is deprecated
• Believing notifications can't be disabled

5. You want to test your website's behavior when the browser homepage is set to 'https://testsite.com' and notifications are disabled. Which code snippet correctly configures the Firefox profile and launches the browser with these settings?

hard

A. profile = FirefoxProfile()
profile.set_preference('browser.startup.homepage', 'https://testsite.com')
profile.set_preference('dom.webnotifications.enabled', False)
profile.update_preferences()
driver = webdriver.Firefox(firefox_profile=profile)

B. profile = FirefoxProfile()
profile.set_preference('browser.startup.homepage', 'https://testsite.com')
profile.set_preference('dom.webnotifications.enabled', 'False')
driver = webdriver.Firefox(profile)

C. profile = FirefoxProfile()
profile.set_preference('browser.startup.homepage', 'https://testsite.com')
profile.set_preference('dom.webnotifications.enabled', False)
driver = webdriver.Firefox(profile=profile)

D. profile = FirefoxProfile()
profile.set_preference('browser.startup.homepage', 'https://testsite.com')
profile.set_preference('dom.webnotifications.enabled', False)
profile.update_preferences()
driver = webdriver.Firefox(profile)

Solution

1. Step 1: Set preferences correctly

   Use set_preference with correct keys and boolean False for notifications.

2. Step 2: Update preferences and pass profile correctly

   Call update_preferences() and pass profile as firefox_profile=profile to WebDriver.

3. Final Answer:

   Code snippet in Option A correctly sets preferences, updates them, and launches Firefox with profile -> Option A

4. Quick Check:

   Set prefs + update + firefox_profile param = profile = FirefoxProfile() profile.set_preference('browser.startup.homepage', 'https://testsite.com') profile.set_preference('dom.webnotifications.enabled', False) profile.update_preferences() driver = webdriver.Firefox(firefox_profile=profile) [OK]

Hint: Call update_preferences() and pass firefox_profile param [OK]

Common Mistakes:

• Passing profile without keyword argument
• Using string 'False' instead of boolean False
• Forgetting update_preferences() call