When using FormatBlock Tool with text inside <div> element the result differs under the different browsers. IE: - cursor placed inside the <div> with no selection: the <div> tag is replaced by the selected heading. - partially selected text: the <div> is split into two and the selection is wrapped with a heading tag. FireFox: - cursor placed inside the <div> with no selection: a heading tag wraps the whole text and the <div> is preserved as parent element. - partially selected text: the <div> is split into two and the selection is wrapped with a heading tag. Chrome: - cursor placed inside the <div> with no selection: the <div> tag is replaced by the selected heading. - partially selected text: the <div> is split into two and the selection is wrapped with a heading tag.