This includes:

- Create multilevel list template for Heading styles

- Add button in the ribbon list styles gallery for applying this list template

-  TOC generated from heading styles associated with list should also include the numbering of the headings (see the related bug 91763). This is not absolutely required for the current item.

--------------------
Currently such list can be added using the following code:
        private void button1_Click(object sender, RoutedEventArgs e)
        {
            ListStyle listStyle = CreateHierarchicalListStyle();

            for (int i = 0; i < 9; i++)
            {
                ListLevelStyle listLevel = listStyle.Levels[i];
                listLevel.HangingIndent = 0;
                listLevel.Indent = 0;
                listLevel.StyleName = RadDocumentDefaultStyles.GetHeadingStyleNameByIndex(i + 1);
            }

            DocumentList documentList = new DocumentList(listStyle, this.radRichTextBox.Document);

            for (int i = 0; i < 9; i++)
            {
                string headingStyleName = RadDocumentDefaultStyles.GetHeadingStyleNameByIndex(i + 1);

                StyleDefinition headingStyle = this.radRichTextBox.Document.StyleRepository.GetValueOrNull(headingStyleName);

                headingStyle.ParagraphStyle.ListId = documentList.ID;
                headingStyle.ParagraphStyle.ListLevel = i;
            }
        }

        private static ListStyle CreateHierarchicalListStyle()
        {
            ListStyle listStyle = new ListStyle();

            for (int i = 0; i < ListStyle.ListLevels; ++i)
            {
                StringBuilder levelText = new StringBuilder();
                for (int j = 0; j < i + 1; ++j)
                {
                    levelText.Append("{" + j + "}.");
                }

                listStyle.Levels.Add(new ListLevelStyle()
                {
                    StartingIndex = 1,
                    NumberingFormat = ListNumberingFormat.Decimal,
                    LevelText = levelText.ToString(),
                });
            }

            return listStyle;
        }

Popups (ImageMiniToolBar and SelectionMiniToolBar) stay on most top (act as if "Always on Top" is set to them) even if they had lost focus. 

Workaround: Attach to LostFocus or LostKeyboardFocus events and hide the toolbar in the handler:
this.radRichTextBox.LostFocus += (sender, e) =>
{
    this.radRichTextBox.SelectionMiniToolBar.Hide();
    this.radRichTextBox.ImageMiniToolBar.Hide();
};

The display mode of all fields is changed to Code, so that the export could work correctly and nested fields would be persisted.
Consider optimizing the algorithm, so that fields take less time to be exported.

Add adorners for selecting table rows, table columns and table cells with single click, similar to the ones in MS Word

The "em" unit will be particularly useful for setting the width of columns/the height of rows in tables.

When there are several instances of RadRichTextBox in the same page/view, it would be nice if only one instance display any selection. 

In the same scenario, the color of the selection of TextBox, for example, changes. Clearing the selection on LostFocus would have been a solution, however control loses focus to the color pickers, comboboxes, etc. from the SelectionMiniToolBar and RadRichTextBoxRibbonUI.

In Word, default tab stops are not present in Paragraph's hanging indent. This leads to difference in the length of the Tab symbol in Word and RadRichTextBox, in cases when hanging is bigger than the default tab stop width.

Implement hyphenation in RadRichTextBox for different languages. 

In MS Word, Heading and the subsequent paragraphs could be collapsed using a small arrow next to the heading. 

This is not preserved in the model.

It would be more user-friendly if the currently edited word (the one containing the caret) is excluded from the real-time spell checking and, if incorrect, is not underlined until the caret leaves the word boundary. Otherwise currently edited word is marked as incorrect while its typing is still in progress.

Changes in a word can immediately mark it as correct (i.e. to remove the red underline), but cannot mark it as incorrect - it's marked as incorrect only after the caret leaves the word.

In MS Word, for example, when you "Save as" PDF, you can choose "options" -> Encrypt the document with a password.

Add support for All Capitals (All caps) and Small Capitals (Small caps) run property. MS Word has such option in Home -> Font -> Dialog Launcher -> Font -> All Caps/Small Caps.

All letters of such runs are visualized as capital letters.

The corresponding elements in OOXML are <w:caps /> and <w:smallcaps />.

- When a floating image is inserted into header/footer the image is clipped. However, if Enter is pressed in the header/footer later, the whole image is shown. Further, if Enter is pressed again, the image is clipped again.
- When floating images are placed in a header or footer, and are positioned outside of the text editor's area, they are not visualized. MS Word visualizes such images as slightly grayed out (similar to watermarks) in normal mode, and always visualizes them in Header/Footer edit mode.

When the current SpanLayoutBox is split (for example by inserting space), the DocumentPosition created with trackDocumentChangeEvents option (with some of the constructor accepting the boolean 'trackDocumentChangeEvents' parameter) jumps back with two symbols.

The unit that is used by default is px. Allow modification to the default unit, say pt.

Add Paragraph property controlling  whether SpacingBefore / SpacingAfter is applied between paragraphs with the same style.

In MS Word, the corresponding option is controlled with "Don't add space between paragraphs of the same style" checkbox in the font properties dialog - and the paragraph spacing after will not be applied. 

In OOXML, it is described with the w:contextualSpacing element. We don't respect this property on import of such files, and the paragraph spacing is bigger.

Common use case for this feature is that when list is applied to multiple paragraphs, Paragraph List style is applied to the items, and this style has "Don't add space between paragraphs of the same style" applied, so the vertical spacing between the items is smaller.

Implement export of RadDocument's Bookmarks to PDF's bookmarks.

RadRichTextBox should have API allowing to set which user can accept or reject the changes. Currently all users can do this.

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

Available in R1 2018 SP2 Release Version.

When the content of an entire row is copied and the caret is inserted in the left most column of a row, then the content of each cell in that row should be overwritten with the contents in the clipboard when pasted.

When such content is pasted just after a table, new row is added and filled with values.

When such content is pasted in paragraph, new table is created.