Heart button in editing, for shortcodes

Hi all,

I’m quite a novice in this, and .. I’m french, so I need a little help please.

I’m trying to reproduce the look of the Aegaeus démo, and I saw in the documentation that normally, I should have an icon in my editing sidebar with a heart.

Like this :

But, i don’t have the heart at all.

How can I do for that issue, please ?
Many thank in advance