diff --git a/src/Hl7.Fhir.Base/CompatibilitySuppressions.xml b/src/Hl7.Fhir.Base/CompatibilitySuppressions.xml
index fb7b173ce..efa8f411b 100644
--- a/src/Hl7.Fhir.Base/CompatibilitySuppressions.xml
+++ b/src/Hl7.Fhir.Base/CompatibilitySuppressions.xml
@@ -14,6 +14,13 @@
     <Right>lib/net8.0/Hl7.Fhir.Base.dll</Right>
     <IsBaselineSuppression>true</IsBaselineSuppression>
   </Suppression>
+  <Suppression>
+    <DiagnosticId>CP0002</DiagnosticId>
+    <Target>M:Hl7.Fhir.Model.Attachment.get_UrlElement</Target>
+    <Left>lib/net8.0/Hl7.Fhir.Base.dll</Left>
+    <Right>lib/net8.0/Hl7.Fhir.Base.dll</Right>
+    <IsBaselineSuppression>true</IsBaselineSuppression>
+  </Suppression>
   <Suppression>
     <DiagnosticId>CP0002</DiagnosticId>
     <Target>M:Hl7.Fhir.Rest.ContentType.BuildContentType(Hl7.Fhir.Rest.ResourceFormat,System.String)</Target>
@@ -42,6 +49,13 @@
     <Right>lib/netstandard2.0/Hl7.Fhir.Base.dll</Right>
     <IsBaselineSuppression>true</IsBaselineSuppression>
   </Suppression>
+  <Suppression>
+    <DiagnosticId>CP0002</DiagnosticId>
+    <Target>M:Hl7.Fhir.Model.Attachment.get_UrlElement</Target>
+    <Left>lib/netstandard2.0/Hl7.Fhir.Base.dll</Left>
+    <Right>lib/netstandard2.0/Hl7.Fhir.Base.dll</Right>
+    <IsBaselineSuppression>true</IsBaselineSuppression>
+  </Suppression>
   <Suppression>
     <DiagnosticId>CP0002</DiagnosticId>
     <Target>M:Hl7.Fhir.Rest.ContentType.BuildContentType(Hl7.Fhir.Rest.ResourceFormat,System.String)</Target>
diff --git a/src/Hl7.Fhir.Base/Model/Generated/Attachment.cs b/src/Hl7.Fhir.Base/Model/Generated/Attachment.cs
index f36e5236b..73f5c6e1c 100644
--- a/src/Hl7.Fhir.Base/Model/Generated/Attachment.cs
+++ b/src/Hl7.Fhir.Base/Model/Generated/Attachment.cs
@@ -1,5 +1,5 @@
 // <auto-generated/>
-// Contents of: hl7.fhir.r5.expansions#5.0.0, hl7.fhir.r5.core#5.0.0
+// Contents of: hl7.fhir.r5.expansions@5.0.0, hl7.fhir.r5.core@5.0.0
 
 using System;
 using System.Collections.Generic;
@@ -159,14 +159,15 @@ public byte[] Data
     /// Uri where the data can be found
     /// </summary>
     [FhirElement("url", InSummary=true, Order=60)]
+    [DeclaredType(Type = typeof(FhirUrl), Since = FhirRelease.R4)]
     [DataMember]
-    public Hl7.Fhir.Model.FhirUrl UrlElement
+    public Hl7.Fhir.Model.FhirUri UrlElement
     {
       get { return _UrlElement; }
       set { _UrlElement = value; OnPropertyChanged("UrlElement"); }
     }
 
-    private Hl7.Fhir.Model.FhirUrl _UrlElement;
+    private Hl7.Fhir.Model.FhirUri _UrlElement;
 
     /// <summary>
     /// Uri where the data can be found
@@ -181,7 +182,7 @@ public string Url
         if (value == null)
           UrlElement = null;
         else
-          UrlElement = new Hl7.Fhir.Model.FhirUrl(value);
+          UrlElement = new Hl7.Fhir.Model.FhirUri(value);
         OnPropertyChanged("Url");
       }
     }
@@ -480,7 +481,7 @@ public override IDeepCopyable CopyTo(IDeepCopyable other)
       if(ContentTypeElement != null) dest.ContentTypeElement = (Hl7.Fhir.Model.Code)ContentTypeElement.DeepCopy();
       if(LanguageElement != null) dest.LanguageElement = (Hl7.Fhir.Model.Code)LanguageElement.DeepCopy();
       if(DataElement != null) dest.DataElement = (Hl7.Fhir.Model.Base64Binary)DataElement.DeepCopy();
-      if(UrlElement != null) dest.UrlElement = (Hl7.Fhir.Model.FhirUrl)UrlElement.DeepCopy();
+      if(UrlElement != null) dest.UrlElement = (Hl7.Fhir.Model.FhirUri)UrlElement.DeepCopy();
       if(SizeElement != null) dest.SizeElement = (Hl7.Fhir.Model.Integer64)SizeElement.DeepCopy();
       if(HashElement != null) dest.HashElement = (Hl7.Fhir.Model.Base64Binary)HashElement.DeepCopy();
       if(TitleElement != null) dest.TitleElement = (Hl7.Fhir.Model.FhirString)TitleElement.DeepCopy();
diff --git a/src/Hl7.Fhir.Specification.STU3.Tests/StructureDefinitionSummaryProviderTest.cs b/src/Hl7.Fhir.Specification.STU3.Tests/StructureDefinitionSummaryProviderTest.cs
index 8a058d5c3..bbed65317 100644
--- a/src/Hl7.Fhir.Specification.STU3.Tests/StructureDefinitionSummaryProviderTest.cs
+++ b/src/Hl7.Fhir.Specification.STU3.Tests/StructureDefinitionSummaryProviderTest.cs
@@ -27,6 +27,16 @@ public void PocoAndSdSummaryProvidersShouldBeEqual()
 
                 AssertEqual(pocoSummary, sdSummary);
             }
+
+            foreach (var item in ModelInfo.OpenTypes)
+            {
+                if (item == typeof(Canonical) || item == typeof(DataRequirement) || item == typeof(Signature) || item == typeof(Timing) || item == typeof(FhirUrl) || item == typeof(UsageContext)) continue;
+                var canonicalResource = ModelInfo.CanonicalUriForFhirCoreType(item);
+                var pocoSummary = pocoSdProvider.Provide(canonicalResource);
+                var sdSummary = sdProvide.Provide(canonicalResource);
+
+                AssertEqual(pocoSummary, sdSummary);
+            }
         }