You cannot stop RH's editor rewriting some of the code. You
can configure RH to edit using a variety of editor's including
Notepad but then you lose the advantages of working in the WYSIWYG
editor, such as dragging a topic to preselected text to create a
hyperlink.
Applying the em tag indicates you want text to be italic
rather than what is defined for the paragraph style in the CSS. If
you change the CSS so that the paragraph changes font and point
size, even written your way that text would still be italic but in
the new font and size. What's the difference?
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