Created Unassigned: Exception from JSON editor [977]

Might be something about our project system causing this:

System.NullReferenceException: Object reference not set to an instance of an object. at Microsoft.VisualStudio.Web.Editor.WebProjectData.<GetAllPersistedPropertiesInternal>d__0.MoveNext() at System.Linq.Enumerable.WhereEnumerableIterator`1.MoveNext() at Microsoft.VisualStudio.JSON.Package.Schema.DropdownMargin.JSONSchemaDropdown.PopulateDropdownEntries() at Microsoft.VisualStudio.JSON.Package.Schema.DropdownMargin.JSONSchemaDropdown..ctor(ITextView textView) at Microsoft.VisualStudio.JSON.Package.Schema.DropdownMargin.JSONSchemaDropdownMargin..ctor(IWpfTextView textView) at Microsoft.VisualStudio.JSON.Package.Schema.DropdownMargin.JSONSchemaDropdownMarginProvider.CreateMargin(IWpfTextViewHost textViewHost, IWpfTextViewMargin containerMargin) at Microsoft.VisualStudio.Text.Utilities.ContainerMargin.<AddMargins>b__2(IWpfTextViewMarginProvider mp) at Microsoft.VisualStudio.Text.Utilities.GuardedOperations.InstantiateExtension[TExtension,TMetadata,TExtensionInstance](Object errorSource, Lazy`2 provider, Func`2 getter)