Wie man per Custom-CSS seine Kollegen am Montag für ein paar Sekunden aus der Fassung bringt. Mir gefällt ja „Hide every 2nd paragraph element on a page“ am besten, die sämtliche Websites auf 'ne subtile Weise zu einem Haufen wirres Zeug zusammenstreichen.

Simply add the definitions to the computers Custom.css file, and watch the fireworks begin. These styles will be applied to every webpage the computer visits in Chrome.
The Custom.css file is usually located here for Macs: ~/Library/Application Support/Google/Chrome/Default/User StyleSheets/Custom.css
And here for PCs: C:/Users/YourUsername/AppData/Local/Google/Chrome/User Data/Default/User StyleSheets/Custom.css

/*Hide every other paragraph element on a page*/
p:nth-child(odd) {
display:none !important;

Co-workers that come in and read a few articles on the internet will wonder what is wrong with writers when none of the stories they read make sense. They might even think the whole internet is in on some prank! Little do they know that they’ve been reading stories with every other paragraph missing.

April Fools Pranks for Developers, hier das AprilFools.css auf GitHub