Related issue:
- https://github.com/gorhill/uBlock/issues/3683
This commit further increases uBO's procedural cosmetic filters
Adguard's cosmetic filter syntax -- specifically those procedural
cosmetic filters where plain CSS selectors appeared following
a procedural oeprator (this was rejected as invalid by uBO).
Also, experimental support for `:watch-attrs` procedural
operator, as discussed in <https://github.com/uBlockOrigin/uBlock-issues/issues/341#issuecomment-449765525>.
Support may be dropped before next release depending on whether
a better solution is suggested.
Additionally, the usual opportunistic refactoring toward ES6
syntax.
A new filtering class has been created: "static extended filtering".
This new class is an umbrella class for more specialized filtering
engines:
- Cosmetic filtering
- Scriptlet filtering
- HTML filtering
HTML filtering is available only on platforms which support modifying
the response body on the fly, so only Firefox 57+ at the moment.
With the ability to modify the response body, HTML filtering has
been introduced: removing elements from the DOM before the source
data has been parsed by the browser.
A consequence of HTML filtering ability is to bring back script tag
filtering feature.
