Onboarding: Notification for Firefox users (4619)

[stracker-phil]

Description

As Firefox behaves different than all other browsers when it comes to loading scripts after page load, the onboarding buttons in the new UI are usually not working in that browser.

The issue is limited to the final "Login" button, which opens the PayPal oAuth popup - all other features do work in Firefox. As a first step to lower the onboarding frustration of Firefox users, we experiment with a new notification that is rendered below the login button in Firefox:

This button may not work in Firefox. Please use another browser, like Chrome, to complete this step.

This new message is displayed in two places:

1. Onboarding wizard, first step (in the "Sandbox" toggle section)
2. Onboarding wizard, last step

Steps to Test

Requirements to test the notification:

1. Ensure the new settings UI is active
2. The current site is disconnected from PayPal, i.e. the onboarding wizard is active

Test the notification:

1. Use Firefox to open the onboarding wizard
2. Expand the "Advanced options" at the bottom of step 1
3. Enable the "Sandbox" toggle
4. Verify that the message is displayed (compare to screenshot below)
5. Follow the same steps in Chrome, Safari, or Edge and confirm there is no message

Screenshot