Hi! Thanks for your interest. I've been doing some thinking in the last couple of days and decided to close source the code for Plume.[1] I'm going to update the website now. I've contributed here[2] for text selection between different blocks if you want to take a look.

Of course, you'll have to implement yourself editing between blocks, undo & redo, copy & paste, etc. For me, a big challenge was to synchronize between the state of underlying plain text and the rendered HTML since Qt's conversion is incredibly inconsistent, it requires some annoying small modifications each time.

BTW, there's a high chance I'll open source Plume in the future. I don't fully trust any non-open source app without a transparent build process. But only after I'm sure I figure out a sustainable monetization source.

[1] https://news.ycombinator.com/item?id=38584960

[2] https://github.com/shaan7/qtdevcon2022-textarea/pull/1