Cosmetic Filters don't apply custom rules

[SergeyZhukovsky]

Description

Original problem is described here https://www.reddit.com/r/brave_browser/comments/lnwon9/brave_native_adblocker_custom_cosmetic_filters/

Steps to Reproduce

1. Go to brave://adblock
2. Add that rule there reddit.com##div
3. Go to reddit.com

Actual result:

The page is not blank

Expected result:

The page is blank

Reproduces how often:

Always

Desktop Brave version:

Android Device details:

• Install type (ARM, x86):
• Device type (Phone, Tablet, Phablet):
• Android version:

Version/Channel Information:

Reproduces on Nightly/Beta only

• Can you reproduce this issue with the current release?
• Can you reproduce this issue with the beta channel?
• Can you reproduce this issue with the nightly channel?

Other Additional Information:

• Does the issue resolve itself when disabling Brave Shields?
• Does the issue resolve itself when disabling Brave Rewards?
• Is the issue reproducible on the latest version of Chrome?

Miscellaneous Information:

[LaurenWags]

labeling as QA/Blocked until uplift is completed

[SergeyZhukovsky]

reopened as it's still a problem

[LaurenWags]

removing QA/Blocked as this should be available for testing in https://github.com/brave/brave-browser/releases/tag/v1.21.68

[LaurenWags]

Verified passed with

Brave | 1.21.68 Chromium: 89.0.4389.58 (Official Build) (x86_64)
-- | --
Revision | 1a139f28ecc27719439e37c6b1533cee999cb802-refs/branch-heads/4389@{#1134}
OS | macOS Version 10.15.7 (Build 19H512)

• ensured that adding/removing reddit.com##div worked as expected

Without Custom Filter	Without Custom Filter

With Custom Filter	With Custom Filter

---

Verification passed on

Brave	1.21.68 Chromium: 89.0.4389.58 (Official Build) (64-bit)
Revision	1a139f28ecc27719439e37c6b1533cee999cb802-refs/branch-heads/4389@{#1134}
OS	Ubuntu 18.04 LTS

• ensured that adding/removing reddit.com##div worked as expected

Without Custom Filter

With Custom Filter

---

Verification passed on

Brave | 1.21.68 Chromium: 89.0.4389.58 (Official Build) (64-bit)
-- | --
Revision | 1a139f28ecc27719439e37c6b1533cee999cb802-refs/branch-heads/4389@{#1134}
OS | Windows 10 OS Version 2004 (Build 19041.804)

• ensured that adding/removing reddit.com##div worked as expected

Without Custom Filter	Without Custom Filter

With Custom Filter	With Custom Filter

[srirambv]

Verification passed on OnePlus 6T with Android 10 running 1.21.70 x64 build

• Verified custom rules work as expected for cosmetic filters

No custom filter	Reddit.com without custom filter

Custom filter	Reddit.com with custom filter

---

Verification passed on Samsung Tab A with Android 10 running 1.21.70 x64 build

• Verified custom rules work as expected for cosmetic filters

No custom filter	Reddit.com without custom filter

Custom filter	Reddit.com with custom filter