There is a big problem with Telerik controls when using national resource files.  Switching from one language to another and again sometimes destroys the user interface. It especially concerns RadCheckBox control. Text, tooltip and probably other properties from one control appear in other control etc. I think it can be a general problem because I also noticed that sometimes Image from one RadButton control appears in other button.

I prepared a set of images which show how it happended in my case. Switching from Default language to Polish language and again and then adding and removing new RadCheckBox completly destroyed user interface in my sample UserControl. This new RadCheckbox was created as a copy of existing RadCheckBox what may be a clue.

I also attached VS2019 project with my sample UserControl.

 

Best regards,

Andrzej

We are experiencing a significant issue with the latest version of Telerik components for WinForms.
The RadTreeView control is affected.
The tree view is populated with nodes.
When nodes are expanded and then scrolled, the +/- indicators are no longer displayed correctly and the elements are also no longer displayed correctly. It even goes so far that no elements are displayed at all (only the root element always seems to remain).

It happens only on environments that we access by remote desktop connection. Never on the local environment till now.

Improve the sorting performance when having equal values in the column.

To reproduce:
public Form1()
{
    InitializeComponent();

    this.radTextBox1.Text = "abcd";
    this.radTextBox2.Text = "abcd";
    this.radTextBoxControl1.Text = "abcd";
    this.radTextBoxControl2.Text = "abcd";

    this.radTextBox2.Multiline = true;
    this.radTextBoxControl2.Multiline = true;

    this.textBox1.Text= "abcd";
    this.textBox2.Text= "abcd";
    this.textBox2.Multiline = true;
}

Workaround: set the Multiline property to true in the Form.Load event.

Second workaround: this.radTextBox2.TextBoxElement.TextBoxItem.Margin = new Padding(-2, 0, 0, 0);

In this case, the SelectedValue property of the RadMultiColumnComboBox control is bound to a custom property. When we select an item from the dropdown, the application hangs. 

To reproduce:
this.radTextBoxControl1.Text = "dog and blue glue";
this.radTextBoxControl1.Size = new Size(50, 65);
this.radTextBoxControl1.Multiline = true;

Workaround:
use RadTextBox.

1. Add RadDropDowlList in form. 
2. Open the items collection and add some items. 
3. After that set the Selected property of one item to true and click OK. 
4. You will see that the change is not saved.

Workaround: 
Set the selected item at run time.

Table rows resize incorrectly when the table spans multiple pages

Team,

 

we did not get any help from public forum,

 

we are expecting in 2026 Q1,

RadControl: Incorrect Font scaling after DPI switch runtime

team,

 

we did not get any help from public forum,

already we commited our stack holders will resolve in 2026 Q1, so please close ASAP.

 

RadControl: Incorrect Font scaling after DPI switch runtime

team,

 

we did not get any help from public forum,

already we commited our stack holders will resolve in 2026 Q1, so please close ASAP.

 

RadFileDialogs: Selecting Large Number of Files is Very Slow

Team,

we did not get any help from public forums, 

we are expecting in 2026Q1,

so please handle it, https://feedback.telerik.com/winforms/1700973-radfiledialogs-selecting-large-number-of-files-is-very-slow

NullReferenceException is called during EndUpdate() under heavy Garbage Collector activity

By default, in the hierarchy RadGridView, filtering the control will show the child row that matches the filtering criteria, along with its parent. The parent row itself could not match the filtering descriptor, which could lead to confusion. We could extend the current functionality of the control and expose a way to hide the parent in this case.

Applied filter operator text remains the same after calling radVirtualGrid1.FilterDescriptors.Clear();

Setting the this.radRichTextEditor1.BackColor does not change the color of the document in LayoutMode.Flow. 

In this scenario, we are using the custom approach from the How to Change PageViewMode for the Nested Levels in RadGridView KB article. When a child row is expanded and we collapse and expand its parent, an exception is thrown.