diff --git a/src/main/java/ru/serega6531/packmate/service/SubscriptionService.java b/src/main/java/ru/serega6531/packmate/service/SubscriptionService.java
index 009e89e..1865a4f 100644
--- a/src/main/java/ru/serega6531/packmate/service/SubscriptionService.java
+++ b/src/main/java/ru/serega6531/packmate/service/SubscriptionService.java
@@ -12,16 +12,15 @@ import org.springframework.web.socket.sockjs.SockJsTransportFailureException;
 import ru.serega6531.packmate.model.pojo.SubscriptionMessage;
 
 import java.io.IOException;
-import java.util.ArrayList;
-import java.util.Collections;
 import java.util.List;
 import java.util.Objects;
+import java.util.concurrent.CopyOnWriteArrayList;
 
 @Service
 @Slf4j
 public class SubscriptionService {
 
-    private final List<WebSocketSession> subscribers = Collections.synchronizedList(new ArrayList<>());
+    private final List<WebSocketSession> subscribers = new CopyOnWriteArrayList<>();
 
     private final ObjectMapper mapper;
 
diff --git a/src/main/java/ru/serega6531/packmate/service/optimization/HttpChunksProcessor.java b/src/main/java/ru/serega6531/packmate/service/optimization/HttpChunksProcessor.java
index a0cfa68..3355144 100644
--- a/src/main/java/ru/serega6531/packmate/service/optimization/HttpChunksProcessor.java
+++ b/src/main/java/ru/serega6531/packmate/service/optimization/HttpChunksProcessor.java
@@ -58,7 +58,8 @@ public class HttpChunksProcessor {
     }
 
     private void checkCompleteChunk(List<Packet> packets, int start) {
-        boolean end = BytesUtils.endsWith(packets.get(packets.size() - 1).getContent(), "\r\n0\r\n\r\n".getBytes());
+        boolean end = Arrays.equals(packets.get(packets.size() - 1).getContent(), "0\r\n\r\n".getBytes()) ||
+                BytesUtils.endsWith(packets.get(packets.size() - 1).getContent(), "\r\n0\r\n\r\n".getBytes());
 
         if (end) {
             processChunk(packets, start);
@@ -122,7 +123,7 @@ public class HttpChunksProcessor {
         int c1 = buf.get();
         int c2 = buf.get();
 
-        if(c1 != '\r' || c2 != '\n') {
+        if (c1 != '\r' || c2 != '\n') {
             log.warn("Failed to merge chunks, chunk trailer is not equal to \\r\\n");
             resetChunk();
             return false;
@@ -162,7 +163,7 @@ public class HttpChunksProcessor {
             if ((b >= '0' && b <= '9') || (b >= 'a' && b <= 'f')) {
                 sb.append((char) b);
             } else if (b == '\r') {
-                if(buf.get() == '\n') {
+                if (buf.get() == '\n') {
                     return Integer.parseInt(sb.toString(), 16);
                 } else {
                     return -1; // после \r не идет \n