Accept null stream filters.

src/Squidex.Infrastructure.GetEventStore/EventSourcing/GetEventStoreSubscription.cs

@@ -30,7 +30,6 @@ namespace Squidex.Infrastructure.EventSourcing
             string streamFilter)
         {
             Guard.NotNull(eventSubscriber, nameof(eventSubscriber));
-            Guard.NotNullOrEmpty(streamFilter, nameof(streamFilter));
 
             this.eventStoreConnection = eventStoreConnection;
             this.eventSubscriber = eventSubscriber;

src/Squidex.Infrastructure.GetEventStore/EventSourcing/ProjectionHelper.cs

@@ -31,6 +31,8 @@ namespace Squidex.Infrastructure.EventSourcing
 
         public static async Task<string> CreateProjectionAsync(this IEventStoreConnection connection, ProjectionsManager projectionsManager, string prefix, string streamFilter = null)
         {
+            streamFilter = streamFilter ?? ".*";
+
             var streamName = ParseFilter(prefix, streamFilter);
 
             if (SubscriptionsCreated.TryAdd(streamName, true))

src/Squidex.Infrastructure/EventSourcing/RetrySubscription.cs

@@ -11,6 +11,8 @@ using System.Threading;
 using System.Threading.Tasks;
 using Squidex.Infrastructure.Tasks;
 
+#pragma warning disable RECS0002 // Convert anonymous method to method group
+
 namespace Squidex.Infrastructure.EventSourcing
 {
     public sealed class RetrySubscription : IEventSubscription, IEventSubscriber
@@ -30,6 +32,7 @@ namespace Squidex.Infrastructure.EventSourcing
         {
             Guard.NotNull(eventStore, nameof(eventStore));
             Guard.NotNull(eventSubscriber, nameof(eventSubscriber));
+            Guard.NotNull(streamFilter, nameof(streamFilter));
 
             this.position = position;