I found a problem regarding text size change and following text selection.
These are the minimal steps to replicate the bug:
* Start WPF demo and select RichTextBox demo
* Select first paragraph under "Overview": from "RadRichTextBox is a control" to "bookmarks and comments."
* From the upper toolbar, change font size to 20
* Scroll down to the second paragraph ("The control can preview... tweaking of images."), you will be only able to select words from the first and fourth line but NOT from the second or the third.
The problem disappears immediately after using another format command or if you change the paragraph text. It seems to me that font size change doesn't invoke a document measure/rearrange.
Thanks for your assistance.