When I started VNote two years ago, I was just a traditional C++ player. So Qt Widgets is the choice. I think it can give me the most freedom and power.

When VNote did not support PlantUML, I used VS Code and plugin to edit and preview PlantUML. It is annoying that I need to scroll to the right element every time I update a line. Why not just hit the element corresponding to current line? So VNote provides this now.