diff --git a/extractor/src/main/java/org/schabi/newpipe/extractor/services/youtube/extractors/YoutubeStreamExtractor.java b/extractor/src/main/java/org/schabi/newpipe/extractor/services/youtube/extractors/YoutubeStreamExtractor.java
index 93bd2121e..b5c6c796a 100644
--- a/extractor/src/main/java/org/schabi/newpipe/extractor/services/youtube/extractors/YoutubeStreamExtractor.java
+++ b/extractor/src/main/java/org/schabi/newpipe/extractor/services/youtube/extractors/YoutubeStreamExtractor.java
@@ -627,7 +627,6 @@ public class YoutubeStreamExtractor extends StreamExtractor {
             "yt\\.akamaized\\.net/\\)\\s*\\|\\|\\s*.*?\\s*c\\s*&&\\s*d\\.set\\([^,]+\\s*,\\s*(:encodeURIComponent\\s*\\()([a-zA-Z0-9$]+)\\(",
             "\\bc\\s*&&\\s*d\\.set\\([^,]+\\s*,\\s*(:encodeURIComponent\\s*\\()([a-zA-Z0-9$]+)\\("
     };
-            ;
 
     private volatile String decryptionCode = "";
 
@@ -788,16 +787,16 @@ public class YoutubeStreamExtractor extends StreamExtractor {
     }
 
     private String decryptSignature(String encryptedSig, String decryptionCode) throws DecryptException {
-        Context context = Context.enter();
+        final Context context = Context.enter();
         context.setOptimizationLevel(-1);
-        Object result;
+        final Object result;
         try {
-            ScriptableObject scope = context.initStandardObjects();
+            final ScriptableObject scope = context.initSafeStandardObjects();
             context.evaluateString(scope, decryptionCode, "decryptionCode", 1, null);
-            Function decryptionFunc = (Function) scope.get("decrypt", scope);
+            final Function decryptionFunc = (Function) scope.get("decrypt", scope);
             result = decryptionFunc.call(context, scope, scope, new Object[]{encryptedSig});
         } catch (Exception e) {
-            throw new DecryptException("could not get decrypt signature", e);
+            throw new DecryptException("Could not get decrypt signature", e);
         } finally {
             Context.exit();
         }