dotnet-core/release-notes/5.0/netstandard2.1/5.0-preview5_System.Collections.Concurrent.md

System.Collections.Concurrent

 namespace System.Collections.Concurrent {
     public class ConcurrentDictionary<TKey, TValue> : ICollection, ICollection<KeyValuePair<TKey, TValue>>, IDictionary, IDictionary<TKey, TValue>, IEnumerable, IEnumerable<KeyValuePair<TKey, TValue>>, IReadOnlyCollection<KeyValuePair<TKey, TValue>>, IReadOnlyDictionary<TKey, TValue> {
+        public bool TryRemove(KeyValuePair<TKey, TValue> item);
     }
 }