Indent for Rich Text fields in Content Manager

Is this a bug?

I would like to be able to indent list items and paragraphs in the Content Manager in Rich Text fields.

Currently I can hit the ‘tab’ button in the Rich Text editor, and it will indent the list item or paragraph appropriately, but when I save the content and pull it back out again, the indentation is gone. No nested indents. Everything is on the same indentation level. The indentation is also gone when I pull up the editor again in the Content Manager. It just disappears.