A feature I like very much from Zim Wiki is that the checkboxes have four states.
Undone / Done / Wont do / Moved. See: https://zim-wiki.org/manual/Help/Check_Boxes.html
Sometimes just two states for a task “Checked / unchecked” is a bit lacking in the information it gives. Adding the other two states gives a more powerful use of the checkboxes.
Would this be possible to implement in Joplin?