Web design, where are you heading? (cz)
Front-end developers beware of HTTP2! You could do serious damage (cz)
Content-visibility: one CSS property that demands fast rendering for everyone (cz)
If you like cards, play FreeCell.
And if you're on a keyboard-equipped PC, play a minimalist snake. It's 1 kB and it's the smallest snake in the world created in JavaScript.
I have also created the smallest Babel library in the world (5 kB). This is a theoretical construct of how to store all the texts in the world in one place.