First of all thank you, it works... kind of

I created the url provider, and the content finder specific for the article entity content.

 public class ArticlePageUrlProvider : DefaultUrlProvider
{
    public ArticlePageUrlProvider(
        IOptionsMonitor<RequestHandlerSettings> requestSettings,
        ILogger<DefaultUrlProvider> logger,
        ISiteDomainMapper siteDomainMapper,
        IUmbracoContextAccessor umbracoContextAccessor,
        UriUtility uriUtility)
        : base(requestSettings, logger, siteDomainMapper, umbracoContextAccessor, uriUtility){}

    public override IEnumerable<UrlInfo> GetOtherUrls(int id, Uri current)
    {
        return base.GetOtherUrls(id, current);
    }

    public override UrlInfo? GetUrl(IPublishedContent content, UrlMode mode, string? culture, Uri current)
    {
        if (content is null)
        {
            return null;
        }

        if (content.ContentType.Alias == "articolo")
        {
            UrlInfo? defaultUrlInfo = base.GetUrl(content, mode, culture, current);
            if (defaultUrlInfo is null)
            {
                return null;
            }

            if (!defaultUrlInfo.IsUrl)
            {
                return defaultUrlInfo;
            }
            else
            {
                var originalUrl = defaultUrlInfo.Text;
                var customUrl = $"articoli{originalUrl}";
                return new UrlInfo(customUrl, true, defaultUrlInfo.Culture);
            }
        }

        return base.GetUrl(content, mode, culture, current);
    }
}

public class ArticleContentFinder : IContentFinder
{
    private readonly IUmbracoContextAccessor _umbracoContextAccessor;

    public ArticleContentFinder(IUmbracoContextAccessor umbracoContextAccessor)
    {
        _umbracoContextAccessor = umbracoContextAccessor;
    }

    public Task<bool> TryFindContent(IPublishedRequestBuilder contentRequest)
    {
        var path = contentRequest.Uri.GetAbsolutePathDecoded();
        if (path.StartsWith("/articoli") is false)
        {
            return Task.FromResult(false); // Not found
        }

        if (!_umbracoContextAccessor.TryGetUmbracoContext(out var umbracoContext))
        {
            return Task.FromResult(false);
        }

        var content = umbracoContext.Content.GetByRoute("/" + path.Split("/").Last());

        if (content is null)
        {
            return Task.FromResult(false);
        }

        contentRequest.SetPublishedContent(content);
        return Task.FromResult(true);
    }
}

And then added them to the main composer:

public class SubscribeToContentServiceSavingComposer : IComposer
{
    public void Compose(IUmbracoBuilder builder)
    {
        builder.Dashboards().Remove<ContentDashboard>();
        builder.UrlProviders().Insert<ArticlePageUrlProvider>();
        builder.ContentFinders().InsertBefore<ContentFinderByUrl, ArticleContentFinder>();

    }
}

And it works.

But now in the backend, when i try to edit an article, it gives me an error:

Stacktrace:

    at System.Uri.CreateThis(String uri, Boolean dontEscape, UriKind uriKind, UriCreationOptions& creationOptions)
   at System.Uri..ctor(String uriString)
   at Umbraco.Extensions.UriExtensions.MakeAbsolute(Uri uri, Uri baseUri)
   at Umbraco.Extensions.UrlProviderExtensions.DetectCollisionAsync(ILogger logger, IContent content, String url, String culture, IUmbracoContext umbracoContext, IPublishedRouter publishedRouter, ILocalizedTextService textService, IVariationContextAccessor variationContextAccessor, UriUtility uriUtility)
   at Umbraco.Extensions.UrlProviderExtensions.GetContentUrlsByCultureAsync(IContent content, IEnumerable`1 cultures, IPublishedRouter publishedRouter, IUmbracoContext umbracoContext, IContentService contentService, ILocalizedTextService textService, IVariationContextAccessor variationContextAccessor, ILogger logger, UriUtility uriUtility, IPublishedUrlProvider publishedUrlProvider)
   at Umbraco.Extensions.UrlProviderExtensions.GetContentUrlsAsync(IContent content, IPublishedRouter publishedRouter, IUmbracoContext umbracoContext, ILocalizationService localizationService, ILocalizedTextService textService, IContentService contentService, IVariationContextAccessor variationContextAccessor, ILogger`1 logger, UriUtility uriUtility, IPublishedUrlProvider publishedUrlProvider)
   at Umbraco.Cms.Web.BackOffice.Mapping.ContentMapDefinition.GetUrls(IContent source)
   at Umbraco.Cms.Web.BackOffice.Mapping.ContentMapDefinition.Map[TVariant](IContent source, ContentItemDisplay`1 target, MapperContext context)
   at Umbraco.Cms.Core.Mapping.UmbracoMapper.Map[TTarget](Object source, Type sourceType, MapperContext context)
   at Umbraco.Cms.Core.Mapping.UmbracoMapper.Map[TTarget](Object source, MapperContext context)
   at Umbraco.Cms.Web.BackOffice.Controllers.ContentController.MapToDisplayWithSchedule(IContent content)
   at Umbraco.Cms.Web.BackOffice.Controllers.ContentController.GetById(Int32 id)
   at lambda_method623(Closure , Object , Object[] )
   at Microsoft.AspNetCore.Mvc.Infrastructure.ActionMethodExecutor.SyncObjectResultExecutor.Execute(IActionResultTypeMapper mapper, ObjectMethodExecutor executor, Object controller, Object[] arguments)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.<InvokeActionMethodAsync>g__Logged|12_1(ControllerActionInvoker invoker)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.<InvokeNextActionFilterAsync>g__Awaited|10_0(ControllerActionInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.Rethrow(ActionExecutedContextSealed context)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.Next(State& next, Scope& scope, Object& state, Boolean& isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.InvokeInnerFilterAsync()
--- End of stack trace from previous location ---
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeNextExceptionFilterAsync>g__Awaited|26_0(ResourceInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)

It does this only on article content. I don't know what to do.

Thank you in advance.

For now, i resolved the problem like this...

I don't think it's the best way to do it, but it works.

I would love to hear if there's a better way.

Thank you in advance.