I'm converting to jupyter from sagenb, and am having trouble finding equivalent interface shortcuts for a couple of features. (a) In sagenb, to get a new cell I can hit a +/wordballoon icon. In jupyter, do I have to go through the pulldown menu or is there some way to get a new cell by mousing inside the notebook? (b) In sagenb, there is a wysiwyg interface for the explanatory-text cells. In jupyter, I'm not finding one; I seem to have to code everything manually in markdown.
Am I missing something, or are those time-saving features gone?