Avoid mutating the issuer set in the options when computing the absolute OIDC metadata address

src/OpenIddict.Abstractions/Resources/OpenIddictResources.resx

@@ -1676,7 +1676,7 @@ To register the OpenIddict core services, reference the 'OpenIddict.Core' packag
     <value>A server configuration containing an invalid issuer was returned.</value>
   </data>
   <data name="ID2098" xml:space="preserve">
-    <value>The issuer returned in the server configuration is not valid.</value>
+    <value>The issuer returned in the server configuration doesn't match the value set in the validation options.</value>
   </data>
   <data name="ID2099" xml:space="preserve">
     <value>No JWKS endpoint could be found in the server configuration.</value>

src/OpenIddict.Abstractions/Resources/xlf/OpenIddictResources.ar.xlf

@@ -473,8 +473,8 @@
         <note />
       </trans-unit>
       <trans-unit id="ID2098">
-        <source>The issuer returned in the server configuration is not valid.</source>
-        <target state="translated">المُصدر الذي تم إرجاعه في إعدادات الخادم غير صالح.</target>
+        <source>The issuer returned in the server configuration doesn't match the value set in the validation options.</source>
+        <target state="needs-review-translation">المُصدر الذي تم إرجاعه في إعدادات الخادم غير صالح.</target>
         <note />
       </trans-unit>
       <trans-unit id="ID2099">

src/OpenIddict.Abstractions/Resources/xlf/OpenIddictResources.de.xlf

@@ -473,8 +473,8 @@
         <note />
       </trans-unit>
       <trans-unit id="ID2098">
-        <source>The issuer returned in the server configuration is not valid.</source>
-        <target state="translated">Der in der Serverkonfiguration zurückgegebene Issuer ist nicht gültig.</target>
+        <source>The issuer returned in the server configuration doesn't match the value set in the validation options.</source>
+        <target state="needs-review-translation">Der in der Serverkonfiguration zurückgegebene Issuer ist nicht gültig.</target>
         <note />
       </trans-unit>
       <trans-unit id="ID2099">

src/OpenIddict.Abstractions/Resources/xlf/OpenIddictResources.es.xlf

@@ -473,8 +473,8 @@
         <note />
       </trans-unit>
       <trans-unit id="ID2098">
-        <source>The issuer returned in the server configuration is not valid.</source>
-        <target state="translated">El emisor devuelto en la configuración del servidor no es válido.</target>
+        <source>The issuer returned in the server configuration doesn't match the value set in the validation options.</source>
+        <target state="needs-review-translation">El emisor devuelto en la configuración del servidor no es válido.</target>
         <note />
       </trans-unit>
       <trans-unit id="ID2099">

src/OpenIddict.Abstractions/Resources/xlf/OpenIddictResources.fr.xlf

@@ -473,8 +473,8 @@
         <note />
       </trans-unit>
       <trans-unit id="ID2098">
-        <source>The issuer returned in the server configuration is not valid.</source>
-        <target state="translated">L'émetteur retourné dans la configuration du serveur n'est pas valide.</target>
+        <source>The issuer returned in the server configuration doesn't match the value set in the validation options.</source>
+        <target state="translated">L'émetteur retourné dans la configuration du serveur ne correspond pas à la valeur définie dans les options de validation.</target>
         <note />
       </trans-unit>
       <trans-unit id="ID2099">

src/OpenIddict.Abstractions/Resources/xlf/OpenIddictResources.gu.xlf

@@ -473,8 +473,8 @@
         <note />
       </trans-unit>
       <trans-unit id="ID2098">
-        <source>The issuer returned in the server configuration is not valid.</source>
-        <target state="translated">સર્વર ગોઠવણીમાં પાછો આપનાર માન્ય નથી.</target>
+        <source>The issuer returned in the server configuration doesn't match the value set in the validation options.</source>
+        <target state="needs-review-translation">સર્વર ગોઠવણીમાં પાછો આપનાર માન્ય નથી.</target>
         <note />
       </trans-unit>
       <trans-unit id="ID2099">

src/OpenIddict.Abstractions/Resources/xlf/OpenIddictResources.hi.xlf

@@ -473,8 +473,8 @@
         <note />
       </trans-unit>
       <trans-unit id="ID2098">
-        <source>The issuer returned in the server configuration is not valid.</source>
-        <target state="translated">सर्वर कॉन्फ़िगरेशन में जारीकर्ता मान्य नहीं है.</target>
+        <source>The issuer returned in the server configuration doesn't match the value set in the validation options.</source>
+        <target state="needs-review-translation">सर्वर कॉन्फ़िगरेशन में जारीकर्ता मान्य नहीं है.</target>
         <note />
       </trans-unit>
       <trans-unit id="ID2099">

src/OpenIddict.Abstractions/Resources/xlf/OpenIddictResources.it.xlf

@@ -473,8 +473,8 @@
         <note />
       </trans-unit>
       <trans-unit id="ID2098">
-        <source>The issuer returned in the server configuration is not valid.</source>
-        <target state="translated">L'emittente restituito nella configurazione del server non è valido.</target>
+        <source>The issuer returned in the server configuration doesn't match the value set in the validation options.</source>
+        <target state="needs-review-translation">L'emittente restituito nella configurazione del server non è valido.</target>
         <note />
       </trans-unit>
       <trans-unit id="ID2099">

src/OpenIddict.Abstractions/Resources/xlf/OpenIddictResources.nl.xlf

@@ -473,8 +473,8 @@
         <note />
       </trans-unit>
       <trans-unit id="ID2098">
-        <source>The issuer returned in the server configuration is not valid.</source>
-        <target state="translated">De uitgever die in de serverconfiguratie is geretourneerd, is niet geldig.</target>
+        <source>The issuer returned in the server configuration doesn't match the value set in the validation options.</source>
+        <target state="needs-review-translation">De uitgever die in de serverconfiguratie is geretourneerd, is niet geldig.</target>
         <note />
       </trans-unit>
       <trans-unit id="ID2099">

src/OpenIddict.Abstractions/Resources/xlf/OpenIddictResources.tr.xlf

@@ -473,8 +473,8 @@
         <note />
       </trans-unit>
       <trans-unit id="ID2098">
-        <source>The issuer returned in the server configuration is not valid.</source>
-        <target state="translated">Sunucu yapılandırmasında döndürülen kuruluş yanıtı geçerli değil.</target>
+        <source>The issuer returned in the server configuration doesn't match the value set in the validation options.</source>
+        <target state="needs-review-translation">Sunucu yapılandırmasında döndürülen kuruluş yanıtı geçerli değil.</target>
         <note />
       </trans-unit>
       <trans-unit id="ID2099">

src/OpenIddict.Abstractions/Resources/xlf/OpenIddictResources.zh-Hans.xlf

@@ -473,8 +473,8 @@
         <note />
       </trans-unit>
       <trans-unit id="ID2098">
-        <source>The issuer returned in the server configuration is not valid.</source>
-        <target state="translated">服务器配置中返回的颁发者无效.</target>
+        <source>The issuer returned in the server configuration doesn't match the value set in the validation options.</source>
+        <target state="needs-review-translation">服务器配置中返回的颁发者无效.</target>
         <note />
       </trans-unit>
       <trans-unit id="ID2099">

src/OpenIddict.Abstractions/Resources/xlf/OpenIddictResources.zh-Hant.xlf

@@ -473,8 +473,8 @@
         <note />
       </trans-unit>
       <trans-unit id="ID2098">
-        <source>The issuer returned in the server configuration is not valid.</source>
-        <target state="translated">伺服器配置中返回的頒發者無效.</target>
+        <source>The issuer returned in the server configuration doesn't match the value set in the validation options.</source>
+        <target state="needs-review-translation">伺服器配置中返回的頒發者無效.</target>
         <note />
       </trans-unit>
       <trans-unit id="ID2099">

src/OpenIddict.Validation/OpenIddictValidationConfiguration.cs

@@ -112,19 +112,20 @@ namespace OpenIddict.Validation
 
                     if (!options.MetadataAddress.IsAbsoluteUri)
                     {
-                        if (options.Issuer is null || !options.Issuer.IsAbsoluteUri)
+                        var issuer = options.Issuer;
+                        if (issuer is null || !issuer.IsAbsoluteUri)
                         {
                             throw new InvalidOperationException(SR.GetResourceString(SR.ID0136));
                         }
 
-                        if (!string.IsNullOrEmpty(options.Issuer.Fragment) || !string.IsNullOrEmpty(options.Issuer.Query))
+                        if (!string.IsNullOrEmpty(issuer.Fragment) || !string.IsNullOrEmpty(issuer.Query))
                         {
                             throw new InvalidOperationException(SR.GetResourceString(SR.ID0137));
                         }
 
-                        if (!options.Issuer.OriginalString.EndsWith("/"))
+                        if (!issuer.OriginalString.EndsWith("/"))
                         {
-                            options.Issuer = new Uri(options.Issuer.OriginalString + "/", UriKind.Absolute);
+                            issuer = new Uri(issuer.OriginalString + "/", UriKind.Absolute);
                         }
 
                         if (options.MetadataAddress.OriginalString.StartsWith("/"))
@@ -133,7 +134,7 @@ namespace OpenIddict.Validation
                                 1, options.MetadataAddress.OriginalString.Length - 1), UriKind.Relative);
                         }
 
-                        options.MetadataAddress = new Uri(options.Issuer, options.MetadataAddress);
+                        options.MetadataAddress = new Uri(issuer, options.MetadataAddress);
                     }
 
                     options.ConfigurationManager = new ConfigurationManager<OpenIdConnectConfiguration>(