Prerequisites

• I verified that this is not a filter issue
  • Filter issues MUST be reported at filter issue tracker
• This is not a support issue or a question
  • Support issues and questions are handled at /r/uBlockOrigin
• I performed a cursory search of the issue tracker to avoid opening a duplicate issue
  • Your issue may already be reported.
• I tried to reproduce the issue when...
  • uBlock Origin is the only extension
  • uBlock Origin with default lists/settings
  • using a new, unmodified browser profile
• I am running the latest version of uBlock Origin
• I checked the documentation to understand that the issue I report is not a normal behavior

Description

I'm impressed with clever use of $domain= by @DandelionSprout DandelionSprout/adfilt#81 (comment), however, in this case you can't use $domain for its original purpose. This can be significant disadvantage as those rules for bad domains can well be untokenizable regex rules which should be narrowed down by $domain. So my proposal here, add $message (or whatsoever suitable English word) to show messages on the strict-blocked page.
Ex.
||badsite.com^$message="The site is blocked for phishing activity!"

Correct me if I'm wrong but I believe this option can and should be ignored on filter parsing - strict-blocked page shows original list name, which means reverse-lookup was done so why doesn't fetch the value of this new option at this step. I wonder if @curbengh, in addition to @DandelionSprout of course, has interest in using this if it's adopted. Other than bad domains, I will use this option for links with tracking parameter. Most users of my lists would have no idea about what to do if such a link is blocked and all my experiences tell that explaining that (i.e. clicking a loupe icon to get a non-tracking link) in README is far from enough.

A specific URL where the issue occurs

Really any URL that can be strict-blocked, but e.g. http://rsalcau.com/ as it's blocked by EL.

Steps to Reproduce

Skipping

Expected behavior:

Messages can be shown on strict-blocked page

Actual behavior:

There's no way other than exploiting $domain=.

Your environment

• uBlock Origin version: 1.28.4
• Browser Name and version: Firefox 79.0
• Operating System and version: Windows 10