To reproduce:
- Add two tabs in a PageView
- Add RadRichTextEditor in the second tab
- Select some text to show the mini toolbar 
- Select the first page.

Workaround
void radPageView1_SelectedPageChanged(object sender, EventArgs e)
{
    if (radPageViewPage2.IsContentVisible == false)
    {
        radRichTextEditor1.RichTextBoxElement.SelectionMiniToolBar.Hide();
    }
}

Import the following code:
<ol>
  <li>Coffee</li>
  <li></li>
  <li>Milk</li>
</ol

To reproduce:
- insert a fragmet from another RichtextEditor like this:
private void Button_Click(object sender, RoutedEventArgs e)
{
radRichTextBox.Document.Sections.Clear();
radRichTextBox.Document.Sections.Add(new Section());

radRichTextBox.Document.CaretPosition.MoveToLastPositionInDocument(); 
radRichTextBox.DocumentEditor.InsertParagraph();
radRichTextBox.DocumentEditor.InsertFragment(new DocumentFragment(radRichTextEditor1.Document));
radRichTextBox.DocumentEditor.InsertParagraph();
}

Workaround:
There is no point of resetting the section in such way. Nevertheless, you can avoid the exception by using one of the following methods:

radRichTextBox.Document.MeasureAndArrangeInDefaultSize();
radRichTextBox.UpdateEditorLayout();

The following parts are with hard coded strings and cannot be localized:

 - Insert Caption (InsertCaptionDialog): Combo boxes for label and separator
 - Paragraph Properties (ParagraphPropertiesDialog): Units of spacing and indentation values (pt)
 - Tab Stops Properties (TabStopsPropertiesDialog): The text of the tabStopsToBeClearedTextBloc
 - Cross references: reference types Figure and Table
 - TOC  and TOF: Heading and Figure, Caption labels
 - Document Ruler: Tooltips
 - FormattingColorPicker: The "No Color" string
- ManageStylesDialog shows items "Modify" and "Delete" with hardcoded text.

To reproduce: add some text to RadRichTextEditor and set the Enabled property to false. You will notice that the text gets bold and blurry. 

Workaround: instead of disabling RadRichTextEditor, use the ReadOnly property.

How to reproduce: check the attached video

Add only a RichTextEditorRibbonBar without any other control on the form. If you run the application you will notice that it loads more than one second. We should investigate if it is possible and how to improve the initialization time.

The issue only reproduces on Windows 10( 1806). Check the attached video showing the result: 

Workaround: Handle the CommandExecuting event this way
private void RadRichTextEditor1_CommandExecuting(object sender, Telerik.WinForms.Documents.RichTextBoxCommands.CommandExecutingEventArgs e)
{
    if (e.Command is ChangeFontFamilyCommand && e.CommandParameter.ToString() == "")
    {
        e.Cancel = true; 
    }
}

Provide functionality allowing a document to be thumbnailed. The customers should be able to export a document to an image.

Workaround: Use attached project. 

Implement commands and UI for producing labels using Mail Merge. 

Behind the scenes this is implemented as Table with the proper number of table columns and rows, and eventually (depending on the setup) NEXT field (https://support.office.com/en-us/article/Field-codes-Next-field-3862fad6-0297-411a-a4e7-6ff5bcf178fd?ui=en-US&rs=en-US&ad=US) - so this will eventually require implementing NEXT field.

Note: In MS Word, this is in Mailings -> Start Mail Merge -> Labels...

If you import a rtf document, it produces a span instances with highlight color property set to ARGB(255,0,0,0).

Workaround:

foreach (Span span in document.EnumerateChildrenOfType<Span>())
{
    if (span.HighlightColor == Color.FromArgb(255, 0, 0, 0))
    {
        span.HighlightColor = Color.Transparent;
    }
}

Workaround:

public class MyInputBehavior : InputBehavior
{
    public MyInputBehavior(DocumentView view)
        : base(view)
    {
  
    }
  
    public override bool ProcessKeyPress(System.Windows.Forms.KeyPressEventArgs e)
    {
        // TO DO: You code here
        e.KeyChar = char.ToUpper(e.KeyChar);
        return true;
        // By commenting the base call you are supresing the default logic
        //return base.ProcessKeyPress(e);
    }
}

Then you should replace the default input behavior by using the following code snippet:
this.richTextBox.DocumentView.InputBehavior = new MyInputBehavior(this.richTextBox.DocumentView);

RadRichTextBox - add import from PDF file.

ADD. Export of Office 2010 dotx document templates.