Colorful Calendar Events

I couldn't figure out how to make this work. I went to the extension and set up a color but then I didn't see if on my calendar event as a choice (existing event or new).

Wasn't expecting this to work, as it kinda didn't seem to do anything. But if you click on the extension, you can set colors to events you have already created. Giving 4/5 stars(would do 4.5 but not an option) because it's a bit of a hassle to not have it on the main calendar and instead having to do it on the calendar page, but I understand this would probably be a pretty hard thing to accomplish lol. Thanks for posting about this on reddit!