Isolate generic cosmetic filters from specific ones in generated styl…

…esheet

Related feedback:
- https://www.reddit.com/r/uBlockOrigin/comments/yzw5pt/

Some CSS4-based selectors are not supported in older browser versions
and this may cause cosmetic filtering to be wholly broken as a result.

The commit here is to isolate generic cosmetic filters from specific
ones in stylesheets such that unsupported CSS4 selectors in generic
cosmetic filters do not cause wholly breakage of cosmetic filtering
on all sites.

src/js/cosmetic-filtering.js

@@ -980,7 +980,6 @@ FilterContainer.prototype.retrieveSpecificSelectors = function(
  options.noSpecificCosmeticFiltering !== true ||
  options.noGenericCosmeticFiltering !== true
  ) {
- const injectedHideFilters = [];
  const specificSet = this.$specificSet;
  const proceduralSet = this.$proceduralSet;
  const exceptionSet = this.$exceptionSet;
@@ -1040,7 +1039,9 @@ FilterContainer.prototype.retrieveSpecificSelectors = function(
  }
 
  if ( specificSet.size !== 0 ) {
- injectedHideFilters.push(Array.from(specificSet).join(',\n'));
+ injectedCSS.push(
+ `${Array.from(specificSet).join(',\n')}\n{display:none!important;}`
+ );
  }
 
  // Some procedural filters are really declarative cosmetic filters, so
@@ -1091,17 +1092,11 @@ FilterContainer.prototype.retrieveSpecificSelectors = function(
  out.exceptedFilters.push(...str.excepted);
  }
  if ( str.s.length !== 0 ) {
- injectedHideFilters.push(str.s);
+ injectedCSS.push(`${str.s}\n{display:none!important;}`);
  }
  }
  }
 
- if ( injectedHideFilters.length !== 0 ) {
- injectedCSS.push(
- `${injectedHideFilters.join(',\n')}\n{display:none!important;}`
- );
- }
-
  // Important: always clear used registers before leaving.
  specificSet.clear();
  proceduralSet.clear();
@@ -1130,7 +1125,7 @@ FilterContainer.prototype.retrieveSpecificSelectors = function(
  const networkFilters = [];
  cacheEntry.retrieve('net', networkFilters);
  if ( networkFilters.length !== 0 ) {
- details.code = networkFilters.join('\n') + '\n{display:none!important;}';
+ details.code = `${networkFilters.join('\n')}\n{display:none!important;}`;
  if ( request.tabId !== undefined ) {
  vAPI.tabs.insertCSS(request.tabId, details);
  }