Toned down interstitials for top-level blocking

Description

Ignoring list errors, there are currently three classes of resources that will be blocked using the Top Level Blocking feature (Search for Top Level Blocking feature spec on GDrive):

1. email trackers with server-side redirections
2. cookie syncing redirect chains
3. bad sites (e.g. typo squatters)

The V1 UX works well for the third category since we don’t want/expect users to ignore our warning and click through to the tracking site.

In the case of the first one however, we expect a high click-through rate because of the implicit intent to visit the destination site (on the other side of the tracker). The risk with warning for this class of trackers is that it will train users to ignore all interstitial warning pages, most of which can lead to very serious harm (e.g. a phishing page blocked by Safe Browsing):

@pes10k tells me that he is less concerned about the third class of sites and that we should optimize the warning interstitials in V2 of the top-level blocking for the first two classes.

Designs

Existing

Revised

Assets

Figma: https://www.figma.com/file/aJu3WGDztEWNZgwQTD9yx2/?node-id=0%3A1

Use Brave’s shared checkbox and button component.

[fmarier]

Here’s an idea for the revised copy:

The page ahead may attempt to track you across sites

This page may be trying to link some of your personal data with a cookie before taking you to your intended destination. You can choose to allow this potential privacy leak and proceed to the next page, or you can block this tracking attempt by going back to the previous page.

[karenkliu]

The new UI hasn’t been done for Android/Desktop yet, so I don’t think this can be closed yet.