Bundled adblock stops working after some time in Youtube and some other sites

[jorgicio]

Description

After some minutes using the browser, the adblock provided by Brave itself stops working after some visits in Youtube (and now fails in Github randomly).

Steps to Reproduce

1. Open Brave.
2. Surfing the web as usual, visiting pages such as Youtube.
3. After some visits, Brave adblock fails and stops working.

Actual result:

Expected result:

The adblock should work as usual, no matter the website (whilst it's not whitelisted, of course).

Reproduces how often:

Always since 1.18.x, installed from official deb releases.

Brave version (brave://version info)

Brave 1.18.77 Chromium: 87.0.4280.101 (Build oficial) (64 bits)
Revisión 9407c80213cda69c2b7abcb4fa8e3f74488f4956-refs/branch-heads/4280@{#1807}
SO Linux
JavaScript V8 8.7.220.29
Flash (Deshabilitado)
User agent Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.101 Safari/537.36
Línea de comandos /opt/brave.com/brave/brave --enable-dom-distiller --disable-domain-reliability --no-pings --extension-content-verification=enforce_strict --extensions-install-verification=enforce --origin-trial-public-key=bYUKPJoPnCxeNvu72j4EmPuK7tr1PAC7SHh8ld9Mw3E=,fMS4mpO6buLQ/QMd+zJmxzty/VQ6B1EUZqoCU04zoRU= --sync-url=https://sync-v2.brave.com/v2 --lso-url=https://no-thanks.invalid --variations-server-url=https://variations.brave.com/seed --enable-features=AutoupgradeMixedContent,WebUIDarkMode,LegacyTLSEnforced,DnsOverHttps,PasswordImport,ReducedReferrerGranularity,PrefetchPrivacyChanges --disable-features=AutofillEnableAccountWalletStorage,AllowPopupsDuringPageUnload,PrivacySettingsRedesign,NotificationTriggers,SmsReceiver,TabHoverCards,PasswordCheck,NetworkTimeServiceQuerying,AutofillServerCommunication,IdleDetection,TextFragmentAnchor,SignedExchangeSubresourcePrefetch,SafeBrowsingEnhancedProtection --flag-switches-begin --flag-switches-end
Ruta ejecutable /opt/brave.com/brave/brave
Ruta del perfil /home/jorgicio/.config/BraveSoftware/Brave-Browser/Default

Version/Channel Information:

Stable version, installed in Ubuntu from official repo as mentioned in its website.

• Can you reproduce this issue with the current release? Yes
• Can you reproduce this issue with the beta channel? No (don't have installed it)
• Can you reproduce this issue with the nightly channel? No (don't have installed it)

Other Additional Information:

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

Miscellaneous Information:

I had to disabled all extensions I installed from the Chrome Web Store, and the issue is the same.

[rebron]

@antonok-edm This isn't a dupe of another youtube ads issue? There seems to be a few of these. Is there enough info in this issue to address?