Improved day numbers with preview of what the day's content is

[jeroenheijmans]

It would be super nice if the various day numbers (especially in the "Podium per day" and "Stats per day" tables) would have some kind of (discoverable, accessible) tooltip or other extension to show what that day was about.

Especially looking at previous years, or even now in January looking back at past month, I struggle to know "what was that day again?". Being able to see "Day 21 'Dirac Dice'" and maybe a line or two fromt he page, would be nice.

Alternatively it could show, with a delay, a small popout window with the day in an iframe?

Need to be careful though as the days in the second table are already clickable button-like links. Not sure how the UX would work. In any case, leaving this trail/issue for myself for next year's edition.

[jeroenheijmans]

Gave this some thought, but it's not trivial to do this. Some concerns:

• Main concern: the feature should play nice with the AoC servers, and not cause malicious/overblown traffic. We can't just fire XHR's upon each hover of a day number.
• Fragility: if we parse part of the HTML pages to find the title and first couple of paragraphs for a preview, that would rely on the html structure, which might change.
• Hard-coding day titles (if even within what's allowed, since that content is copyrighted) doesn't work for the year when puzzles are coming out freshly.

I'm letting this issue sit until at least fall, not spending time on it until I at least know there will be a next edition of AoC at all.