The options “bold” and “italic” are not displayed. But testing I noticed that is not displayed only in edit normal view; if we toggle to edit full view then these options are displayed.
I’ve checked the tools which are used by default on the rich-text editor and both (bold and italic) are included in these default options. To force a situation I’ve excluded all tools and included manually bold and italic and the result is the same.
This is by design, as we were running out of space in the button row in a recent version of CS. As Alan mentions, simple keyboard shortcuts are available for these buttons. Also maximize will reveal these buttons as well.