Brave Shield blocks necessary cookies from dartpad.dev

[gaetschwartz]

Description

Steps to Reproduce

1. Go to https://dart.dev/codelabs/iterables#example-using-a-for-in-loop
2. Make sure Brave shield is enabled
3. You can see that the Shield blocks something (cookies form dartpad.dev) that makes the embedded https://dartpad.dev to not work.

You can see here https://dart.dev/tools/dartpad/troubleshoot#embedded-dartpads-dont-appear that we need to have cookies enabled for this website to work because it uses Local Storage. Plus, dartpad.dev & dart.dev are mmanaged by the same team (Dart developers) so it's not really 3rd party.

Actual result:

With Brave Shield enabled

Expected result:

With Brave Shield disabled

Reproduces how often:

Easily reproduced

Brave version (brave://version info)

Brave	1.16.72 Chromium: 86.0.4240.183 (Official Build) (64-bit)
Revision	0b568b034b8f7994697cb341eeca5979b84151cc-refs/branch-heads/4240@{#1374}
OS	Windows 10 OS Version 2009 (Build 19042.572)

Version/Channel Information:

• Can you reproduce this issue with the current release? Yes
• Can you reproduce this issue with the beta channel? Haven't tested
• Can you reproduce this issue with the nightly channel? Haven't tested

Other Additional Information:

• Does the issue resolve itself when disabling Brave Shields? Yes
• Does the issue resolve itself when disabling Brave Rewards? No
• Is the issue reproducible on the latest version of Chrome? No as Brave Shield is Brave exclusive

Miscellaneous Information:

[pes10k]

hi @gaetschwartz , just wanted to let you know that #8514 is our general plan to address these issues. If the 3p frame really does need persistant storage, than #8514 won't fix, but if it just needs to be able to store things for the lifetime of the session, that'll address

[gaetschwartz]

@pes10k It would indeed fix it because it just needs it for the session. Thanks for the feedback ! I will close the issue and reopen it if #8514 doesn't fix it !