Ouch, thats horrible. What's that, like 5-8 pixels of space to write? Completely unusable there. So lets come up with an idea, and its going to be quite difficult to come to a resolution how you go about solving this UX and UI issue. Looks like to me if you trim the format buttons and tags, you'll be able to see and save roughly 50 pixels or so? Thats still not a lot but hey, its good enough.
Hey @Giorgio-Chiodi can you do me a favor and screenshot Convoe's composer and see what type of result you get as well. I'm not 100% sure of how it looks with that particular phone you have and based on that I can help come up with some clever ideas.