diff --git a/src/cheogram/java/eu/siacs/conversations/services/QuickConversationsService.java b/src/cheogram/java/eu/siacs/conversations/services/QuickConversationsService.java
index cf79c67c755b6f970a621f06616a9e2949aba52f..d58e590cf0eab0eab2e59078db03eaf5c029eefb 100644
--- a/src/cheogram/java/eu/siacs/conversations/services/QuickConversationsService.java
+++ b/src/cheogram/java/eu/siacs/conversations/services/QuickConversationsService.java
@@ -114,8 +114,8 @@ public class QuickConversationsService extends AbstractQuickConversationsService
 
     protected Set<String> gateways(final Account account) {
         return Stream.concat(
-            account.getGateways("pstn").stream(),
-            account.getGateways("sms").stream()
+            ImmutableList.copyOf(account.getGateways("pstn")).stream(),
+            ImmutableList.copyOf(account.getGateways("sms")).stream()
         ).map(a -> a.getJid().asBareJid().toString()).collect(Collectors.toSet());
     }