I want to add a fixed top toolbar to my editorjs like:

I do not find any documentation how to do it on: https://editorjs.io/

Of course, i already googled it, but not really a good result.

To make the toolbar is not an issue, as you can see on the screenshot. But i don't know how i can handle, when i click on the button, that the focused block will be formatted.

Does anyone knows how I can do that?