Pull request - 2817: AG-58002 Reject rules with unknown or unsupported modifiers in MV3

Squashed commit of the following:

commit 4b2cdb2
Author: Maxim Topciu <mtopciu@adguard.com>
Date:   Mon Aug 24 16:52:42 2026 +0300

    AG-58002 Reject rules with unknown or unsupported modifiers in MV3

commit fb9d02c
Merge: 6cc6b6c 2e7176d
Author: Maxim Topciu <mtopciu@adguard.com>
Date:   Mon Aug 24 16:33:30 2026 +0300

    AG-58002 Merge master into Browser Extension fix branch

commit 6cc6b6c
Author: Maxim Topciu <mtopciu@adguard.com>
Date:   Mon Aug 24 11:08:53 2026 +0300

    AG-58002 Reject rules with unknown or unsupported modifiers in MV3

Author: maximtop

CHANGELOG.md

@@ -14,10 +14,13 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - `$removeparam` rules without a value (e.g. `||example.org^$removeparam`)
   blocked the whole site in MV3 instead of removing all query parameters [#3602].
 - Unanchored `$urltransform` substitutions did not apply to query strings in MV3 [#3600].
+- Rules with unknown or unsupported modifiers were applied as broader blocking
+  or allow rules in MV3 [AdguardFilters#238305].
 
 [#3598]: https://github.com/AdguardTeam/AdguardBrowserExtension/issues/3598
 [#3602]: https://github.com/AdguardTeam/AdguardBrowserExtension/issues/3602
 [#3600]: https://github.com/AdguardTeam/AdguardBrowserExtension/issues/3600
+[AdguardFilters#238305]: https://github.com/AdguardTeam/AdguardFilters/issues/238305
 
 ## [5.5.1.0] - 2026-08-21