In April last year, I had a lot of fun doing a live coding session for the WordPress Block Editor. The demo was hosted by Birgit Pauli-Haack as part of the Gutenberg Times, Live Q & A series. I paired with Zac Gordon, an educator at JavaScript for WordPress with a ton of Javascript online courses for WordPress developers. This is what we covered:
We explored how to customize format controls like bold or italics and extend the block toolbar with your control allowing to change the color of the selected text.
References
You can find show notes and the full transcript at Gutenberg Times.
There is also a repository available with the code used in the session: https://github.com/gziolo/gutenberg-times.