story
Here's another example: GNOME shell uses JavaScript and CSS, and it's pretty straightforward to understand. Was looking at the code of a plugin to hide the workspace switcher popup and tried a few things to instead reduce the animation time to something that does not necessarity stick around over my windows too long to bother me when I want to view the content beneath. Took and few hours but I got it configured decently, and "live reloaded" it to get the effect instantly. Here I reused my JavaScript knowledge to solve it; if it wasn't so easy due to my previous unrelated knowledge I probably wouldn't have invested any time in it.