I’m not sure if I have the right to give this theme any unique name, since I don’t know CSS and glued this theme out of the three themes I like most:
Obsidian Red Graphite
Obsidian dark rmx - v202009222210 - 0.9.00 by _ph
Typora Pie
Colors for graph in dark theme taken from theme of Nick Milo (sorry, I don’t know name of it).
Initially, I wanted to adapt the Pie theme, which I often used in typora, but in the end the themes listed above were so good that I could not choose any one.
If you liked the previous version of fonts (monospaced in edit mode, serif in two preview mode), you can change the value of the parameters font-size and font-family at the beginning of the file:
in the menu the color of headers has been corrected (after the update, instead of white on a dark gray background, it became gray on a dark gray background)
completed checklist items are painted with accent color (found a color filter in the settings and turned it off)
corrected the color of the text in the buttons in the menu (everything was fine in the dark theme, but in the light theme there was a gray font on a gray background, the button text was almost invisible)