When ContentAreaMode="Div" RadEditor's Content Area's width automatically re-sizes with the content. If width is applied to reContentArea div element, the problem is resolved.

Actual behavior: by placing a long word or pasting an image larger than the content area's dimensions, its width is automatically expanded. (see ActualBehavior.png)

Expected Behavior: the content area's width should remain unchanged despite word length and pasted image dimensions. (see ExpectedBehavior.png)