Mark procedural filters with pseudo-elements selector as invalid

Related issue:
uBlockOrigin/uBlock-issues#2786

Author: gorhill

src/js/static-filtering-parser.js

@@ -3297,10 +3297,9 @@ class ExtSelectorCompiler {
         if ( this.astHasType(parts, 'Error') ) { return; }
         if ( this.astHasType(parts, 'Selector') === false ) { return; }
         if ( this.astIsValidSelectorList(parts) === false ) { return; }
-        if (
-            this.astHasType(parts, 'ProceduralSelector') === false &&
-            this.astHasType(parts, 'ActionSelector') === false
-        ) {
+        if ( this.astHasType(parts, 'ProceduralSelector') ) {
+            if ( this.astHasType(parts, 'PseudoElementSelector') ) { return; }
+        } else if ( this.astHasType(parts, 'ActionSelector') === false ) {
             return this.astSerialize(parts);
         }
         const r = this.astCompile(parts);