René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"An item with the same key has already been added.","articleBody":"Sometimes we get the following exception:\r\n\r\n```\r\nSystem.ArgumentException: An item with the same key has already been added.\r\n   at System.ThrowHelper.ThrowArgumentException(ExceptionResource resource)\r\n   at System.Collections.Generic.Dictionary`2.Insert(TKey key, TValue value, Boolean add)\r\n   at ICSharpCode.SharpDevelop.Dom.NRefactoryResolver.NRefactoryASTConvertVisitor.VisitAttributes(IList`1 attributes, ClassFinder context)\r\n   at ICSharpCode.SharpDevelop.Dom.NRefactoryResolver.NRefactoryASTConvertVisitor.ConvertAttributes(AttributedNode from, AbstractEntity to)\r\n   at ICSharpCode.SharpDevelop.Dom.NRefactoryResolver.NRefactoryASTConvertVisitor.VisitTypeDeclaration(TypeDeclaration typeDeclaration, Object data)\r\n   at ICSharpCode.NRefactory.Ast.TypeDeclaration.AcceptVisitor(IAstVisitor visitor, Object data)\r\n   at ICSharpCode.NRefactory.Ast.AbstractNode.AcceptChildren(IAstVisitor visitor, Object data)\r\n   at ICSharpCode.SharpDevelop.Dom.NRefactoryResolver.NRefactoryASTConvertVisitor.VisitNamespaceDeclaration(NamespaceDeclaration namespaceDeclaration, Object data)\r\n   at ICSharpCode.NRefactory.Ast.NamespaceDeclaration.AcceptVisitor(IAstVisitor visitor, Object data)\r\n   at ICSharpCode.NRefactory.Ast.AbstractNode.AcceptChildren(IAstVisitor visitor, Object data)\r\n   at ICSharpCode.SharpDevelop.Dom.NRefactoryResolver.NRefactoryASTConvertVisitor.VisitCompilationUnit(CompilationUnit compilationUnit, Object data)\r\n\r\n```\r\nUnfortunatelly I cannot provide scenario to reproduce, this issue is quite rare.","author":{"url":"https://github.com/lomovod","@type":"Person","name":"lomovod"},"datePublished":"2017-01-25T13:16:21.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":0},"url":"https://github.com/525/NRefactory/issues/525"}