diff --git a/csharp/extractor/Semmle.Extraction.CSharp/Entities/Types/Type.cs b/csharp/extractor/Semmle.Extraction.CSharp/Entities/Types/Type.cs
index 25c8926e3e0..8c93d630d15 100644
--- a/csharp/extractor/Semmle.Extraction.CSharp/Entities/Types/Type.cs
+++ b/csharp/extractor/Semmle.Extraction.CSharp/Entities/Types/Type.cs
@@ -250,41 +250,44 @@ namespace Semmle.Extraction.CSharp.Entities
         /// </summary>
         public void PopulateGenerics()
         {
-            if (Symbol is null || !NeedsPopulation || !Context.ExtractGenerics(this))
-                return;
-
-            var members = new List<ISymbol>();
-
-            foreach (var member in Symbol.GetMembers())
-                members.Add(member);
-            foreach (var member in Symbol.GetTypeMembers())
-                members.Add(member);
-
-            // Mono extractor puts all BASE interface members as members of the current interface.
-
-            if (Symbol.TypeKind == TypeKind.Interface)
+            Context.PopulateLater(() =>
             {
-                foreach (var baseInterface in Symbol.Interfaces)
+                if (Symbol is null || !NeedsPopulation || !Context.ExtractGenerics(this))
+                    return;
+
+                var members = new List<ISymbol>();
+
+                foreach (var member in Symbol.GetMembers())
+                    members.Add(member);
+                foreach (var member in Symbol.GetTypeMembers())
+                    members.Add(member);
+
+                // Mono extractor puts all BASE interface members as members of the current interface.
+
+                if (Symbol.TypeKind == TypeKind.Interface)
                 {
-                    foreach (var member in baseInterface.GetMembers())
-                        members.Add(member);
-                    foreach (var member in baseInterface.GetTypeMembers())
-                        members.Add(member);
+                    foreach (var baseInterface in Symbol.Interfaces)
+                    {
+                        foreach (var member in baseInterface.GetMembers())
+                            members.Add(member);
+                        foreach (var member in baseInterface.GetTypeMembers())
+                            members.Add(member);
+                    }
                 }
-            }
 
-            foreach (var member in members)
-            {
-                Context.CreateEntity(member);
-            }
+                foreach (var member in members)
+                {
+                    Context.CreateEntity(member);
+                }
 
-            if (Symbol.BaseType is not null)
-                Create(Context, Symbol.BaseType).PopulateGenerics();
+                if (Symbol.BaseType is not null)
+                    Create(Context, Symbol.BaseType).PopulateGenerics();
 
-            foreach (var i in Symbol.Interfaces)
-            {
-                Create(Context, i).PopulateGenerics();
-            }
+                foreach (var i in Symbol.Interfaces)
+                {
+                    Create(Context, i).PopulateGenerics();
+                }
+            }, preserveDuplicationKey: false);
         }
 
         public void ExtractRecursive(TextWriter trapFile, IEntity parent)
diff --git a/csharp/extractor/Semmle.Extraction/Context.cs b/csharp/extractor/Semmle.Extraction/Context.cs
index 6694757f0d8..a6442758daf 100644
--- a/csharp/extractor/Semmle.Extraction/Context.cs
+++ b/csharp/extractor/Semmle.Extraction/Context.cs
@@ -153,9 +153,9 @@ namespace Semmle.Extraction
         /// Enqueue the given action to be performed later.
         /// </summary>
         /// <param name="toRun">The action to run.</param>
-        public void PopulateLater(Action a)
+        public void PopulateLater(Action a, bool preserveDuplicationKey = true)
         {
-            var key = GetCurrentTagStackKey();
+            var key = preserveDuplicationKey ? GetCurrentTagStackKey() : null;
             if (key is not null)
             {
                 // If we are currently executing with a duplication guard, then the same
diff --git a/csharp/ql/test/library-tests/csharp7/TupleExpr.expected b/csharp/ql/test/library-tests/csharp7/TupleExpr.expected
index ed5c61051c1..66ceb61382b 100644
--- a/csharp/ql/test/library-tests/csharp7/TupleExpr.expected
+++ b/csharp/ql/test/library-tests/csharp7/TupleExpr.expected
@@ -40,8 +40,8 @@
 | CSharp7.cs:87:18:87:34 | (..., ...) | CSharp7.cs:87:18:87:34 | (String,String) | 1 | CSharp7.cs:87:30:87:33 | "X2" |
 | CSharp7.cs:88:9:88:24 | (..., ...) | CSharp7.cs:87:18:87:34 | (String,String) | 0 | CSharp7.cs:88:14:88:15 | String t2 |
 | CSharp7.cs:88:9:88:24 | (..., ...) | CSharp7.cs:87:18:87:34 | (String,String) | 1 | CSharp7.cs:88:22:88:23 | String t3 |
-| CSharp7.cs:95:18:95:38 | (..., ...) | file://:0:0:0:0 | (Int32,String) | 0 | CSharp7.cs:95:19:95:19 | 1 |
-| CSharp7.cs:95:18:95:38 | (..., ...) | file://:0:0:0:0 | (Int32,String) | 1 | CSharp7.cs:95:22:95:37 | "TupleExprNode1" |
+| CSharp7.cs:95:18:95:38 | (..., ...) | CSharp7.cs:95:18:95:38 | (Int32,String) | 0 | CSharp7.cs:95:19:95:19 | 1 |
+| CSharp7.cs:95:18:95:38 | (..., ...) | CSharp7.cs:95:18:95:38 | (Int32,String) | 1 | CSharp7.cs:95:22:95:37 | "TupleExprNode1" |
 | CSharp7.cs:96:18:96:43 | (..., ...) | CSharp7.cs:96:18:96:43 | (Int32,(String,Int32)) | 0 | CSharp7.cs:96:19:96:19 | 1 |
 | CSharp7.cs:96:18:96:43 | (..., ...) | CSharp7.cs:96:18:96:43 | (Int32,(String,Int32)) | 1 | CSharp7.cs:96:22:96:42 | (..., ...) |
 | CSharp7.cs:96:22:96:42 | (..., ...) | file://:0:0:0:0 | (String,Int32) | 0 | CSharp7.cs:96:23:96:38 | "TupleExprNode2" |
@@ -82,11 +82,11 @@
 | CSharp7.cs:223:9:223:18 | (..., ...) | CSharp7.cs:213:5:213:17 | (Int32,Double) | 1 | CSharp7.cs:223:17:223:17 | _ |
 | CSharp7.cs:224:9:224:18 | (..., ...) | CSharp7.cs:213:5:213:17 | (Int32,Double) | 0 | CSharp7.cs:224:10:224:10 | _ |
 | CSharp7.cs:224:9:224:18 | (..., ...) | CSharp7.cs:213:5:213:17 | (Int32,Double) | 1 | CSharp7.cs:224:17:224:17 | Double y |
-| CSharp7.cs:283:40:283:61 | (..., ...) | file://:0:0:0:0 | (Int32,String) | 0 | CSharp7.cs:283:41:283:48 | access to property Key |
-| CSharp7.cs:283:40:283:61 | (..., ...) | file://:0:0:0:0 | (Int32,String) | 1 | CSharp7.cs:283:51:283:60 | access to property Value |
-| CSharp7.cs:285:18:285:34 | (..., ...) | file://:0:0:0:0 | (Int32,String) | 0 | CSharp7.cs:285:23:285:23 | Int32 a |
-| CSharp7.cs:285:18:285:34 | (..., ...) | file://:0:0:0:0 | (Int32,String) | 1 | CSharp7.cs:285:33:285:33 | String b |
-| CSharp7.cs:287:18:287:31 | (..., ...) | file://:0:0:0:0 | (Int32,String) | 0 | CSharp7.cs:287:23:287:23 | Int32 a |
-| CSharp7.cs:287:18:287:31 | (..., ...) | file://:0:0:0:0 | (Int32,String) | 1 | CSharp7.cs:287:30:287:30 | String b |
-| CSharp7.cs:289:18:289:27 | (..., ...) | file://:0:0:0:0 | (Int32,String) | 0 | CSharp7.cs:289:23:289:23 | Int32 a |
-| CSharp7.cs:289:18:289:27 | (..., ...) | file://:0:0:0:0 | (Int32,String) | 1 | CSharp7.cs:289:26:289:26 | String b |
+| CSharp7.cs:283:40:283:61 | (..., ...) | CSharp7.cs:95:18:95:38 | (Int32,String) | 0 | CSharp7.cs:283:41:283:48 | access to property Key |
+| CSharp7.cs:283:40:283:61 | (..., ...) | CSharp7.cs:95:18:95:38 | (Int32,String) | 1 | CSharp7.cs:283:51:283:60 | access to property Value |
+| CSharp7.cs:285:18:285:34 | (..., ...) | CSharp7.cs:95:18:95:38 | (Int32,String) | 0 | CSharp7.cs:285:23:285:23 | Int32 a |
+| CSharp7.cs:285:18:285:34 | (..., ...) | CSharp7.cs:95:18:95:38 | (Int32,String) | 1 | CSharp7.cs:285:33:285:33 | String b |
+| CSharp7.cs:287:18:287:31 | (..., ...) | CSharp7.cs:95:18:95:38 | (Int32,String) | 0 | CSharp7.cs:287:23:287:23 | Int32 a |
+| CSharp7.cs:287:18:287:31 | (..., ...) | CSharp7.cs:95:18:95:38 | (Int32,String) | 1 | CSharp7.cs:287:30:287:30 | String b |
+| CSharp7.cs:289:18:289:27 | (..., ...) | CSharp7.cs:95:18:95:38 | (Int32,String) | 0 | CSharp7.cs:289:23:289:23 | Int32 a |
+| CSharp7.cs:289:18:289:27 | (..., ...) | CSharp7.cs:95:18:95:38 | (Int32,String) | 1 | CSharp7.cs:289:26:289:26 | String b |
diff --git a/csharp/ql/test/library-tests/csharp7/TupleTypes.expected b/csharp/ql/test/library-tests/csharp7/TupleTypes.expected
index 55c27e756f4..d958ad60e4d 100644
--- a/csharp/ql/test/library-tests/csharp7/TupleTypes.expected
+++ b/csharp/ql/test/library-tests/csharp7/TupleTypes.expected
@@ -1,10 +1,13 @@
 | (Int32,(String,Int32)) | (int, (string, int)) | ValueTuple<int, (string, int)> | 2 | 0 | CSharp7.cs:96:19:96:19 | Item1 |
-| (Int32,(String,Int32)) | (int, (string, int)) | ValueTuple<int, (string, int)> | 2 | 1 | CSharp7.cs:96:22:96:42 | Item2 |
+| (Int32,(String,Int32)) | (int, (string, int)) | ValueTuple<int, (string, int)> | 2 | 1 | CSharp7.cs:102:22:102:46 | Item2 |
 | (Int32,Double) | (int, double) | ValueTuple<int, double> | 2 | 0 | CSharp7.cs:213:6:213:8 | Item1 |
 | (Int32,Double) | (int, double) | ValueTuple<int, double> | 2 | 1 | CSharp7.cs:213:11:213:16 | Item2 |
 | (Int32,Int32) | (int, int) | ValueTuple<int, int> | 2 | 0 | CSharp7.cs:62:10:62:10 | Item1 |
 | (Int32,Int32) | (int, int) | ValueTuple<int, int> | 2 | 1 | CSharp7.cs:62:17:62:17 | Item2 |
+| (Int32,String) | (int, string) | ValueTuple<int, string> | 2 | 0 | CSharp7.cs:95:19:95:19 | Item1 |
+| (Int32,String) | (int, string) | ValueTuple<int, string> | 2 | 1 | CSharp7.cs:95:22:95:37 | Item2 |
 | (String,Int32) | (string, int) | ValueTuple<string, int> | 2 | 0 | CSharp7.cs:82:17:82:17 | Item1 |
+| (String,Int32) | (string, int) | ValueTuple<string, int> | 2 | 0 | CSharp7.cs:101:19:101:38 | Item1 |
 | (String,Int32) | (string, int) | ValueTuple<string, int> | 2 | 1 | CSharp7.cs:82:23:82:23 | Item2 |
 | (String,String) | (string, string) | ValueTuple<string, string> | 2 | 0 | CSharp7.cs:87:19:87:27 | Item1 |
 | (String,String) | (string, string) | ValueTuple<string, string> | 2 | 1 | CSharp7.cs:87:30:87:33 | Item2 |