Telerik UI for ASP.NET AJAX

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Telerik UI for ASP.NET AJAX

Release History

UI for ASP.NET AJAX R1 2021 SP1 (version 2021.1.224)

February 24, 2021


  • Kendo Scripts Upgrade from 2020.3.915 to 2021.1.119
  • Upgrade wizards updates wrong web.config in case several configs exist


  • RadButton's focus state styling is missing in Bootstrap


  • The Diagram appears broken when its parent container is initially hidden


  • Keyboard navigation in Drawer
  • Drawer itemClick event is not thrown if there are more than 1 HTML elements in the template


  • RadEditor within UpdatePanel TD tag context menu throws Permission Denied under IE


  • Replace Gantt custom treelist implementation with the actual TreeList component
  • Add sort order icon in treelist header
  • Show more information in the dragClue when dragging in treelist
  • Incorrect titlebar appearance in Gantt dialogs
  • Increase width of TextBox, Numeric and DatePicker controls in default edit form dialog
  • Focus the buttons inside a confirm dialog when opened
  • The Gantt appears broken when its parent container is initially hidden
  • Not properly sized resizable columns in Gantt's TreeList view on less than 480px screen width
  • Unable to preserve edited Gantt task name on pressing Enter or clicking on treelist in Edge 42
  • Gantt save event not fired when dropping a task to make it child of another task
  • Unable to edit Gantt TreeList nodes on mobile browsers
  • Gantt with editable reorder set to false and navigatable set to true throws a JavaScript error
  • Drag and drop of the first root item before itself results in Cannot read property 'orderId' of null


  • ArgumentOutOfRangeException is thrown when using Persian (fa-IR) culture for the application


  • The Chart appears broken when its parent container is initially hidden
  • Bar Chart date axis: The first day of the week should be taken from the current culture


  • MultiColumnComboBox dropdown gets transparent when the PdfViewer is available on the page


  • MultiSelect WAI-ARIA the div element with role "listbox" requires at least one owned "option" element
  • MultiSelect highlightFirst:false focuses the first item if autoBind is false
  • MultiSelect - caret position cannot be changed through click after filtering
  • MultiSelect selected items are not announced by screen readers


  • The disabled Pager's arrows inside the PDFViewer doesn't have aria-disabled="true" attribute
  • Empty title attribute of PDFViewer zoom level combobox
  • Zooming with no toolbar throws JS error
  • If you choose "Fit to Width" and load another file in the PDF Viewer, it sets the "Automatic Width" in the ComboBox, but the one applied is actually "Fit to Width"
  • Using fromFile method with no file loaded causes JS errors


  • Introduced mechanism for loading custom font files when importing TrueType fonts.
  • Handled import of documents containing Outlines (Bookmarks) containing Actions with an empty dictionary.
  • Standard fonts do not respect font style and font weight when the original font is not found.
  • ArgumentException is thrown when merging a document containing Link annotation without action or destination.
  • NullReferenceException is thrown when parsing an object stream that contains endObj keyword.
  • Paragraph bullets are not painted as dots.
  • IndexOutOfRangeException is thrown when importing a document containing a specific image encoded with JBIG2Decode.


  • NullReferenceException is thrown if EnableConfigurationPanel is set to True and no data is bound to the PivotGrid


  • Exported CSV should have an extra comma-separated field in place of empty cells.
  • The TabColor is lost on import/export scenario and in case it is set in the code.


  • Spreadsheet exports corrupt XLSX when containing an empty Sheet with a focused A1 cell
  • Spreadsheet comments are not properly exported in XLSX
  • Comments in the Spreadsheet are not properly displayed in frozen columns scenario
  • Incorrect DatePicker popup rendering in Spreadsheet with multiple vertically merged cells
  • Spreadsheet list validation should consider "1,2,3,.." as a numeric list
  • When using a custom cell editor in the Spreadsheet along with keyboard navigation value selection is not limited to the cell with the custom cell editor
  • Spreadsheet formula input and cell editor don't have max-width
  • While creating a formula, cannot navigate through already present tokens
  • Incorrect Spreadsheet validation dropdown auto-resize
  • Incorrect Spreadsheet filtering with Turkish letters
  • Values copied from Spreadsheet and pasted in Excel are duplicated
  • Spreadsheet cell content, copied with Cut/Copy toolbar/context menu buttons, is pasted as HTML to cells in Edit mode or to cells in another Spreadsheet


  • Keyboard navigation in Timeline


  • Introduced support for Run properties as part of the Structured Document Tag properties.
  • Image size is not respected when importing HTML.
  • ArgumentException is thrown when importing invalid font sizes from DOCX.
  • Bullets are not exported correctly to PDF.
  • Floating image is positioned incorrectly when exporting to PDF in some cases when the image is added right after a run.
  • Empty paragraphs height is lower than expected in PDF export scenarios.

Telerik UI for ASP.NET AJAX

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