Several sites breaking with "Block Outside Intrusion Into LAN" filter #3426

Prerequisites

• This is NOT a YouTube, Facebook, Twitch or a shortener/hosting site report. These sites MUST be reported by clicking their respective links.
• I read and understand the policy about what is a valid filter issue.
• I verified that this issue is not a duplicate. (Search here to find out.)
• I did not remove any of the default filter lists, or I have verified that the issue was not caused by removing any of the default lists.
• I did not enable additional filter lists, or I have verified that the issue still occurs without enabling additional filter lists.
• I do not have custom filters/rules, or I have verified that the issue still occurs without custom filters/rules.
• I am not using uBlock Origin along with other content blockers.
• I have verified that the web browser's built-in content blocker/tracking protection, network wide/DNS blocking, or my VPN is not causing the issue.
• I have verified that other extensions are not causing the issue.
• If this is about a breakage or detection, I have verified that it is caused by uBlock Origin and isn't a site issue.
• I did not answer truthfully to ALL the above checkboxes.

URL(s) where the issue occurs.

https://github.com/uBlockOrigin/uAssets (broken css)
https://www.aliexpress.com/ (broken images)
https://math.stackexchange.com/ (broken css)

Description

Several sites are breaking with the "Block Outside Intrusion Into LAN"

this mainly seems to affect sites that use a separate domain for images/css.

this occurs when the only filter list enabled is the "Block Outside Intrusion Into LAN" list.

The extension pane for ublock also shows the content domains blocked on the broken sites, and disabling that specific list fixes the issue (ie. the issue is not caused by some other method of blocking content)
eg.

• githubassets.com for github
• sstatic.net for SE/SO
• alicdn.com and aliexpress-media.com for aliexpress

I have experienced the issue with other sites as well, however I do not recall them at the moment.

This issue is occurs only in the following conditions:

• on android (unsure if android is a prerequisite to cause this or not; have not been able to test with these other conditions on other platforms)
• when the blocked content from the cdn domain has not been cached by the browser (ie. was not previously loaded when in a working state)
• using mobile data (possibly due to only having an ipv6 address and no ipv4 address? needs to be investigated further.)

Other extensions used

• Bitwarden
• Bypass Paywalls Clean
• ClearURLs
• Dark Reader
• Decentraleyes
• Bitwarden

Screenshot(s)

Configuration

uBlock Origin: 1.60.0
Firefox Mobile: 129
filterset (summary):
 network: 18827
 cosmetic: 20666
 scriptlet: 1439
 html: 18
listset (total-discarded, last-updated):
 removed:
  ublock-filters: null
  ublock-badware: null
  ublock-privacy: null
  ublock-unbreak: null
  ublock-quick-fixes: null
  adguard-mobile: null
  easylist: null
  easyprivacy: null
  urlhaus-1: null
  plowe-0: null
 added:
  block-lan: 64-0, 24m
 default:
  user-filters: 0-0, never
filterset (user): [empty]
trustedset:
 added: [array of 19 redacted]
userSettings:
 webrtcIPAddressHidden: true
hiddenSettings: [none]
supportStats:
 allReadyAfter: 854 ms (selfie)
 maxAssetCacheWait: 396 ms
 cacheBackend: indexedDB