IdentityServer4 dotnet7 produce exception

when using Automaper 10.1.1, with identityserver4 and .net 7, identityserver4 is the last free version of IdentityServer and doesn't work with a higher version of AutoMapper where this issue is resolved in this link: Issue.
Automapper 10 + identity server 4 + dotnet 7
simply when I hit /.well-known/openid-configuration I got this exception

ArgumentException: GenericArguments[0], 'System.Char', on 'T MaxFloat[T](System.Collections.Generic.IEnumerable`1[T])' violates the constraint of type 'T'.
System.RuntimeType.ValidateGenericArguments(MemberInfo definition, RuntimeType[] genericArguments, Exception e)
System.Reflection.RuntimeMethodInfo.MakeGenericMethod(Type[] methodInstantiation)
AutoMapper.TypeDetails+<>c__DisplayClass28_1.<BuildPublicNoArgExtensionMethods>b__10(MethodInfo extensionMethod)
System.Linq.Enumerable+WhereSelectArrayIterator<TSource, TResult>.MoveNext()
System.Linq.Enumerable+ConcatIterator<TSource>.MoveNext()
System.Linq.Enumerable.SelectManyIterator<TSource, TCollection, TResult>(IEnumerable<TSource> source, Func<TSource, IEnumerable<TCollection>> collectionSelector, Func<TSource, TCollection, TResult> resultSelector)+MoveNext()
System.Linq.Enumerable+WhereSelectEnumerableIterator<TSource, TResult>.MoveNext()
System.Collections.Generic.HashSet<T>.UnionWith(IEnumerable<T> other)
System.Linq.Enumerable+UnionIterator<TSource>.FillSet()
System.Linq.Enumerable+UnionIterator<TSource>.ToArray()
AutoMapper.TypeDetails.BuildPublicNoArgExtensionMethods(IEnumerable<MethodInfo> sourceExtensionMethodSearch)
AutoMapper.TypeDetails..ctor(Type type, ProfileMap config)
AutoMapper.ProfileMap.TypeDetailsFactory(Type type)
AutoMapper.Internal.LockingConcurrentDictionary<TKey, TValue>+<>c__DisplayClass2_1.<.ctor>b__1()
System.Lazy<T>.ViaFactory(LazyThreadSafetyMode mode)
System.Lazy<T>.ExecutionAndPublication(LazyHelper executionAndPublication, bool useDefaultConstructor)
System.Lazy<T>.CreateValue()
AutoMapper.Internal.LockingConcurrentDictionary<TKey, TValue>.GetOrAdd(TKey key)
AutoMapper.ProfileMap.CreateTypeDetails(Type type)
AutoMapper.TypeMapFactory.CreateTypeMap(Type sourceType, Type destinationType, ProfileMap options, bool isReverseMap)
AutoMapper.ProfileMap.BuildTypeMap(IConfigurationProvider configurationProvider, ITypeMapConfiguration config)
AutoMapper.ProfileMap.Register(IConfigurationProvider configurationProvider)
AutoMapper.MapperConfiguration.Seal()
AutoMapper.MapperConfiguration..ctor(MapperConfigurationExpression configurationExpression)
AutoMapper.MapperConfiguration..ctor(Action<IMapperConfigurationExpression> configure)
IdentityServer4.EntityFramework.Mappers.IdentityResourceMappers..cctor()
// Put your source/destination types here

I tryed all Higher versions and I get another exception because identity server 4 requires AutoMapper version>=10 and <11, in this case I got this exception:

System.MissingMethodException: Method not found: '!2 AutoMapper.IMappingExpressionBase`3.ConstructUsing(System.Linq.Expressions.Expression`1<System.Func`2<!0,!1>>)'.
   at IdentityServer4.EntityFramework.Mappers.ClientMapperProfile..ctor()
   at System.RuntimeType.CreateInstanceOfT()

I found a solution

1. Just copy/paste these 2 projects and create own libraries:

IdentityServer4.EntityFramework

IdentityServer4.EntityFramework.Storage

2. Bump Mapper version and fix Nullable reference types in IdentityServer4.EntityFramework.Storage lib.
3. Remove packages from code and replace with your libraries.
   

.well-known/openid-configuration now works for me.

I also saw this problem yesterday - spent a lot of time looking for a solution but couldnt.
I decided to downgrade .net to 6.0 then it worked - though, the requirements of IS4.EF.Storage mention support to .net 7.0

> Maybe you should look at Duende.IdentityServer

This is new company by creators of IS4. Probably the issue has been resolved there. Switching from IS4 to Duende shouldnt be difficult due to their similarity

As an update from the answer by @Tapac, you can use this package which has the updated AutoMapper

• https://www.nuget.org/packages/Cnblogs.IdentityServer4.EntityFramework.Storage/

Also, this is discussed in detail here: https://github.com/IdentityServer/IdentityServer4/issues/5486

You can install new version of Automapper directly to your top level projects and solution would use them.