Fixing issue #13865 (i.e. Rich text link picker not resolving correct variant when using .ValueFor()). (#13889)

(cherry picked from commit 451d1cec6a)

src/Umbraco.Core/Extensions/PublishedElementExtensions.cs

@@ -134,6 +134,27 @@ public static class PublishedElementExtensions
 
     #endregion
 
+    #region CheckVariation
+    /// <summary>
+    /// Method to check if VariationContext culture differs from culture parameter, if so it will update the VariationContext for the PublishedValueFallback.
+    /// </summary>
+    /// <param name="publishedValueFallback">The requested PublishedValueFallback.</param>
+    /// <param name="culture">The requested culture.</param>
+    /// <param name="segment">The requested segment.</param>
+    /// <returns></returns>
+    private static void EventuallyUpdateVariationContext(IPublishedValueFallback publishedValueFallback, string? culture, string? segment)
+    {
+        IVariationContextAccessor? variationContextAccessor = publishedValueFallback.VariationContextAccessor;
+
+        //If there is a difference in requested culture and the culture that is set in the VariationContext, it will pick wrong localized content.
+        //This happens for example using links to localized content in a RichText Editor.
+        if (!string.IsNullOrEmpty(culture) && variationContextAccessor?.VariationContext?.Culture != culture)
+        {
+            variationContextAccessor!.VariationContext = new VariationContext(culture, segment);
+        }
+    }
+    #endregion
+
     #region Value<T>
 
     /// <summary>
@@ -174,6 +195,8 @@ public static class PublishedElementExtensions
     {
         IPublishedProperty? property = content.GetProperty(alias);
 
+        EventuallyUpdateVariationContext(publishedValueFallback, culture, segment);
+
         // if we have a property, and it has a value, return that value
         if (property != null && property.HasValue(culture, segment))
         {

src/Umbraco.Core/Models/PublishedContent/IPublishedValueFallback.cs

@@ -5,6 +5,11 @@ namespace Umbraco.Cms.Core.Models.PublishedContent;
 /// </summary>
 public interface IPublishedValueFallback
 {
+    /// <summary>
+    /// VariationContextAccessor that is not required to be implemented, therefore throws NotImplementedException as default.
+    /// </summary>
+    IVariationContextAccessor VariationContextAccessor { get { throw new NotImplementedException(); } set { throw new NotImplementedException(); } }
+
     /// <summary>
     ///     Tries to get a fallback value for a property.
     /// </summary>

src/Umbraco.Core/Models/PublishedContent/PublishedValueFallback.cs

@@ -20,6 +20,8 @@ public class PublishedValueFallback : IPublishedValueFallback
         _variationContextAccessor = variationContextAccessor;
     }
 
+    public IVariationContextAccessor VariationContextAccessor { get { return _variationContextAccessor; } }
+
     /// <inheritdoc />
     public bool TryGetValue(IPublishedProperty property, string? culture, string? segment, Fallback fallback, object? defaultValue, out object? value) =>
         TryGetValue<object>(property, culture, segment, fallback, defaultValue, out value);