Suppose I want to add the following to that calendar:
1. two little emojis (or ASCII art) at the top to scroll among months. Bound to left/right arrow keys, and also clickable with mouse. This is a common feature of the calendar widgets I've seen.
2. clickable mutable daily content. So if I peruse my calendar and spot an error I can click to select, fix it, then click off it to update it.
Can this be achieved only using shell scripting?