Make the image loading async and consider reducing their size like MS Word

Show substitute image when the image from the document cannot be rendered 

RichTextEditor: Lists are always exported to HTML with Verdana font. 

Changing the normal style or setting the DocumentInheritsDefaultStyleSettings has no effect.

Support for math type equations. 

Drop a RadRichTextEditor and a WinForms button on a form.
Set the text of the button to "&Activate" and show a message box in the button click handler.
Run the program, and type some text - the button is activated whenever you try to type the letter "a" in the editor.

Workarround: Inherit RadRichTextEditor and override IsInputChar method
protected override bool IsInputChar(char charCode)
{
    return true;
}

************** Exception Text **************
System.NullReferenceException: Object reference not set to an instance of an object.
   at Telerik.WinForms.Documents.UI.UIProviders.WatermarkUIProvider.Arrange(UILayerUpdateContext uILayerUpdateContext)
   at Telerik.WinForms.Documents.UI.Layers.ProviderUILayerBase.ArrangeChildren()
   at Telerik.WinForms.Documents.UI.DocumentPrintPresenter.ArrnageUILayers()
   at Telerik.WinForms.Documents.UI.DocumentPrintPresenter.MeasureOverride(SizeF availableSize)
   at Telerik.WinControls.RadElement.MeasureCore(SizeF availableSize)
   at Telerik.WinControls.RadElement.Measure(SizeF availableSize)
   at Telerik.WinControls.RadElement.MeasureChildren(SizeF availableSize)
   at Telerik.WinControls.RichTextEditor.UI.FrameworkElement.MeasureOverride(SizeF availableSize)
   at Telerik.WinControls.RadElement.MeasureCore(SizeF availableSize)
   at Telerik.WinControls.RadElement.Measure(SizeF availableSize)
   at Telerik.WinControls.Layouts.ContextLayoutManager.UpdateLayout()
   at Telerik.WinForms.Documents.UI.DocumentPrintPresenter.Telerik.WinForms.RichTextEditor.IDocumentEditorPresenter.UpdateLayout()
   at Telerik.WinForms.RichTextEditor.RadRichTextBox.<>c__DisplayClass3.<UpdateEditorLayout>b__2()
   at Telerik.WinForms.RichTextEditor.RadRichTextBox.UpdateEditorLayout(Boolean focusCarret, Boolean updateCaretSize, Boolean async)
   at Telerik.WinForms.RichTextEditor.RadRichTextBox.set_ActiveEditorPresenter(IDocumentEditorPresenter value)
   at Telerik.WinForms.RichTextEditor.RadRichTextBox.Telerik.WinControls.UI.IPrintable.BeginPrint(RadPrintDocument sender, PrintEventArgs args)
   at Telerik.WinControls.UI.RadPrintDocument.OnBeginPrint(PrintEventArgs e)
   at System.Drawing.Printing.PrintDocument._OnBeginPrint(PrintEventArgs e)
   at System.Drawing.Printing.PrintController.Print(PrintDocument document)
   at System.Drawing.Printing.PrintDocument.Print()
   at System.Windows.Forms.PrintPreviewControl.ComputePreview()
   at System.Windows.Forms.PrintPreviewControl.CalculatePageInfo()
   at System.Windows.Forms.Control.InvokeMarshaledCallbackDo(ThreadMethodEntry tme)
   at System.Windows.Forms.Control.InvokeMarshaledCallbackHelper(Object obj)
   at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
   at System.Windows.Forms.Control.InvokeMarshaledCallback(ThreadMethodEntry tme)
   at System.Windows.Forms.Control.InvokeMarshaledCallbacks()


To reproduce: please refer to the attached gi file demonstrating how to replicate the problem with the Demo application.

Workaround:

        private void radRichTextEditor1_CommandExecuting(object sender, Telerik.WinForms.Documents.RichTextBoxCommands.CommandExecutingEventArgs e)
        {
            if (e.Command  is ChangeIntegratedWatermarkTypeCommand && this.radRichTextEditor1.LayoutMode!= Telerik.WinForms.Documents.Model.DocumentLayoutMode.Paged)
            {
                e.Cancel = true; 
            }
        }

Add support for Paragraph and Page borders.

Add an option for users to be able to export embedded images as Content IDs.
CID images work by attaching the image to the email sent and then using standard HTML image tags that reference that image to eventually embed it in the email when the user opens it.

Workaround:

        public TextEditorRadForm()
        {
            InitializeComponent();
            ((RadForm)this.radRichTextEditor1.RichTextBoxElement.InsertCaptionDialog).Controls["radRichTextEditorLabel"].Text = "";
        }

To reproduce: add a RadRichTextEditor with ribbon UI. Set the RichTextEditorRibbonBar's theme to Fluent at design time. When you run the application you will notice that the theme is not properly applied to the backstage view.

Workaround: ThemeResolutionService.ApplicationThemeName = "Fluent";

To reproduce:
- Drop RadRichTextEditor  to a form.
- Set the theme to FluentDark. 

Workaround:
radRichTextEditor1.ChangeTextForeColor(Color.White);

or

public void SetBackColor()
{
    this.radRichTextEditor1.RichTextBoxElement.BackColor = Color.White;
    Theme theme = ThemeRepository.FindTheme("TelerikMetroBlue");

    foreach (var styleGroup in theme.StyleGroups)
    {
        foreach (PropertySettingGroup settingGroup in styleGroup.PropertySettingGroups)
        {
            if (settingGroup.Selector.Value == "Telerik.WinControls.RichTextEditor.UI.Page")
            {
                foreach (PropertySetting property in settingGroup.PropertySettings)
                {
                    if (property.Name == "BackColor")
                    {
                        property.Value = System.Drawing.Color.White;
                    }
                }
            }
            if (settingGroup.Selector.Value == "Telerik.WinControls.RichTextEditor.UI.HeaderFooterContainer")
            {
                foreach (PropertySetting property in settingGroup.PropertySettings)
                {
                    if (property.Name == "OverlayColor")
                    {
                        property.Value = System.Drawing.Color.White;
                    }
                }
            }
        }
    }

}

- There should be a formatting symbol for the character

- Pressing Ctrl+Shift+Space should insert the character (standard MS Word shortcut)

- Import from docx should be implemented

- The symbol should be treated as a separator between words when spell-checking

When the copied text doesn't contain any formating the Keep Text Only paste option should be applied.

To reproduce:

1.Add some text to RadRichTextEditor.
2.Copy an image from a Word document and paste it to the RadRichTextEditor.
3.Export the document content with RtfFormatProvider.

When you try to open the exported .rtf file via WordPad, you will notice that the image is not loaded. Please refer to the attached files created by MS Word and RadRichTextEditor.

When you load a HTML file where the image is not loaded properly and you try to export RadRichTextEditor's document to a pdf, an error occurs. 

Workaround:
If the image doesn't exist you can skip loading in the document. Thus, exporting to pod at a later moment won't produce an error. You can use the HtmlImportSettings.LoadImageFromUrl event and handle the image loading:

    Sub New()

        ' This call is required by the designer.
        InitializeComponent()

        Dim provider As HtmlFormatProvider = New HtmlFormatProvider()

        Dim htmlImportSettings As HtmlImportSettings = New HtmlImportSettings() 
        AddHandler htmlImportSettings.LoadImageFromUrl, AddressOf LoadImageFromUrl
        provider.ImportSettings = htmlImportSettings

        Using inputStream As FileStream = File.OpenRead("..\..\Email HTML.html")
            Me.RadRichTextEditor1.Document = provider.Import(inputStream)
        End Using

    End Sub

    Private Sub LoadImageFromUrl(sender As Object, e As LoadImageEventArgs)
        e.Handled = True
    End Sub

To reproduce:
- Add a word, press tab the add another word.
- Export the document using HtmlFormatProvider.
- Import the same document.
- The tab is interpreted like 7 spaces.