Specific filter list has no rules loaded unless its URL is changed to be the same when parsed but different when in plaintext #3476

Prerequisites

• I verified that this is not a filter list issue. Report any issues with filter lists or broken website functionality in the uAssets issue tracker.
• This is NOT a YouTube, Facebook or Twitch report. These sites MUST be reported by clicking their respective links.
• This is not a support issue or a question. For support, questions, or help, visit /r/uBlockOrigin.
• I performed a cursory search of the issue tracker to avoid opening a duplicate issue.
• The issue is not present after disabling uBO in the browser.
• I checked the documentation to understand that the issue I am reporting is not normal behavior.

I tried to reproduce the issue when...

• uBO is the only extension.
• uBO uses default lists and settings.
• using a new, unmodified browser profile.

Description

This specific filterlist - a.k.a., this specific filter list (the problem
only happens with this one) - will not be loaded at all in uBO. it will get added as a custom filter list but 0 filters will be recognized. However, it WILL load if I change the URL to be the same when parsed but different in plaintext (e.g. Doing weird path name trickery tricks https://easylist-downloads.adblockplus.org/.%2E/exceptionrules.txt, including the port number https://easylist-downloads.adblockplus.org:443/exceptionrules.txt)

A specific URL where the issue occurs.

extension://odfafepnkmbhccpbejgmiehpchacaeak/dashboard.html#3p-filters.html

Steps to Reproduce

1. Add this filter list into uBO
2. Watch 0 out of 0 filters be recognized

Expected behavior

1. Add this filter list
2. Watch the full ~600k filters be recognized

Actual behavior

1. Add this filter list
2. 0 out of 0 filters were recognized

Workaround:

1. Add the filter list, but do something to make the parsed URL same but plaintext URL different (e.g. including the 443 port number)
2. It works

uBO version

1.61.2

Browser name and version

Microsoft Edge Dev 133.0.2992.0

Operating System and version

Microsoft Windows Version 23H2 (OS Build 22631.4541) © Microsoft Corporation. All rights reserved.