Please allow Font size in pixels that affects editor and preview to have more than 30 pixels. I have poor eyesight and 30 is not that big size for me. I can read it but bigger would feel much more comfortable. At the moment H3 size is appropriate for me. And apart from that, bigger screen size allows bigger font size even when someone has correct eyesight. It is just much more comfortable to read long texts with bigger font size.
How about 60 or 100 pixels limit. And does it really need to be a limit?