In some complex script languages, like Telugu and Thai language, some characters are grouped (e.g. consonants + vowels) in new grapheme. 

For example, type 'p' in Telugu - 'జ', followed by 'ో' - they are combined in new grapheme - 'జో', or paste the following Thai grapheme: ชื

UI correctly visualizes this, but:
- Text measuring assumes that the grapheme width is equal to the sum of the widths of its parts (characters), which is not correct. Selection and caret position are scrambled because of this.
- There are document positions between  the grapheme parts (characters), but shouldn't.
- When the caret is before the grapheme, deleting with "Delete" key deletes the grapheme in multiple steps (character by character), but should delete it in single step. Deleting with "Backspace" works correctly.
- There are some unsupported combinations in some languages. For example in Thai, typing 'z' then 'y' will produce grapheme, but typing 'w' then 'y' will not produce grapheme, and the 'y' should be ignored.

KeyNotFoundException is thrown when loading a document with a custom bibliographic style applied.

As a workaround, you can change the current bibliographic style to one of the predefined styles before the export of the document.

...
this.radRichTextBox.CommandExecuting += RadRichTextBox_CommandExecuting;
...

...
private void RadRichTextBox_CommandExecuting(object sender, CommandExecutingEventArgs e)
{
    if (e.Command is SaveCommand)
    {
        this.radRichTextBox.ChangeBibliographicStyle(new APAFifthEditionStyle());
    }
}

Korean language input does not work correctly on Windows 11 versions after 22H2 (OS Build 22621.1265).

This is related to an update to the Microsoft Input Method Editor (IME). The workaround is to enable the "Previous version of Microsoft IME" (check the attached screenshots for the steps).

Importing a document with block-level content controls from XAML causes them to become corrupt. If you scroll to a position in which the said control is only partially visible a NullReferenceException is thrown.

A possible workaround would be to initially save the document as a DOCX (just exporting it to DOCX will not fix the issue as the information is already corrupt).

Another way to reproduce this issue:

1. Create a new document and insert a Rich Text Content Control.

2. Save the document as a XAML file.

3. Reopen the XAML file.

4. Move the caret inside the Content Control.

5. Try to insert a new line by hitting Enter - no new line is added as the content control is marked as Inline Level after the import in step 3.

Case 2: 

Create a document with TOC where the content control of the TOC contains some other inlines.