Entire page exceptions in $document or $content modifiers

[seia-soto]

⚠️ Warning This doesn't mean that we decided to implement $document or $content as entire page exceptions.

Currently, the adblocker library is following uBlock Origin's static filtering and cosmetic filtering syntax to provide an ad-blocking capability to the community while partially supporting aliases, syntax dialects, and many more. However, we get into the discussion to the modifier behavior in #3897 ($replace modifier support).

uBlock Origin has the following direction according to their wiki:

It is not supported. The document option used with an exception filter is to disable uBO. The document option in static exception filters is for the sake of "acceptable ads" support, which uBO does not support.
The reason it is not supported is to be sure that users explicitly disable uBO themselves if they wish (through Trusted sites feature), not having some external filter list decide for them.
https://github.com/gorhill/uBlock/wiki/Static-filter-syntax#document-for-entire-page-exception

As stated in the very first of this issue, we're following uBlock Origin's behavior. Therefore, we don't support entire page exceptions using any kind of modifiers like $document and $content. Only behavior we support is to specify the request type. At the time, this means the matching logic is to change and our position in longer term is also to change.