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An alert message is thrown when adding a tag by typing it in the Tags field in edit mode of an item

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Article Number000094380
EnvironmentProduct: Sitefinity
Version: 5.x, 6.x, 7.x, 8.x, 9.x, 10.x, 11.x
OS: All supported OS versions
Database: All supported Microsoft SQL Server versions
Question/Problem Description
An alert message is thrown when adding a tag by typing it in the "Tags" field in edit mode of an item.
Steps to ReproduceThe issue is reproducible in the old backend UI. In the new AdminApp, it is working as expected:

1. Create two tags that partially contain the same letters, for example:
-- ret
-- Retail
2. Create a Category (name of choosing) and add a synonym to it that contains "ret", for example, "Retail"
3. Open an item for edit (does not matter what type it is) and try to add "ret" as a tag by typing it in the field and waiting for Autocomplete.
Clarifying Information
Error MessageType : System.ArgumentNullException, mscorlib, Version=, Culture=neutral, PublicKeyToken=b77a5c561934e089
Message : Value cannot be null.
Parameter name: localizableItem
Source : Telerik.Sitefinity.Model
Help link :
ParamName : localizableItem
Data : System.Collections.ListDictionaryInternal
TargetSite : Telerik.Sitefinity.Model.Localization.RequiredLocalizablePropertyAttribute GetRequiredPropertyAttribute(Telerik.Sitefinity.Localization.ILocalizable)
HResult : -2147467261
Stack Trace : at Telerik.Sitefinity.Localization.ILocalizableExtensions.GetRequiredPropertyAttribute(ILocalizable localizableItem)
at Telerik.Sitefinity.Localization.ILocalizableExtensions.GetAvailableCultures(ILocalizable localizableItem, CultureInfo defaultLanguage, Boolean alwaysReturnDefault)
at Telerik.Sitefinity.Taxonomies.Web.Services.Common.TaxonServiceHelper.CreateWcfTaxonObject(Taxon taxon, TaxonomyManager manager, WcTaxonDataFlags flags, Type dataItemType)
at Telerik.Sitefinity.Taxonomies.Web.Services.FlatTaxonService.GetTaxaInternal(String taxonomyId, String provider, String sortExpression, Int32 skip, Int32 take, String filter, String itemType, String mode, String siteContextMode)
at SyncInvokeGetTaxa(Object , Object[] , Object[] )
at System.ServiceModel.Dispatcher.SyncMethodInvoker.Invoke(Object instance, Object[] inputs, Object[]& outputs)
at System.ServiceModel.Dispatcher.DispatchOperationRuntime.InvokeBegin(MessageRpc& rpc)
at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage5(MessageRpc& rpc)
at System.ServiceModel.Dispatcher.ImmutableDispatchRuntime.ProcessMessage11(MessageRpc& rpc)
at System.ServiceModel.Dispatcher.MessageRpc.Process(Boolean isOperationContextSet)

Additional Info:

Requested URL : http://localhost:1727/Sitefinity/Services/Taxonomies/FlatTaxon.svc/cb0f3a19-a211-48a7-88ec-77495c0f5374/?skip=0&take=20&sortExpression=Title
Defect/Enhancement NumberBug 259622
For more information about Bug 259622, see
None at this time.
1. For content types that support the new AdminApp backend UI, switching to it should allow you to use the filed for adding tags:
Progress Sitefinity Documentation, Toggle between new and classic experience

2. For the rest of types that do not yet support the new AdminApp backend UI, add tags without using the filed for typing.
References to Other Documentation:
Progress Sitefinity Documentation, Toggle between new and classic experience
Last Modified Date2/12/2019 9:41 AM