Scratch
From Screamer Wiki
Scratch is a platform website that has its first prototype created in 2003, the site primarily targets at children to get to learn about coding by placing out 10 colored-blocks which functions the game,
The site, of course, has a game-community where people have their game published into the platform, However, somehow some projects provides screamers to scare the viewer.
According to Scratch Wiki, the article stated that "screamer is a project where an image suddenly appears along with a random sound (traditionally a scream — hence the name "screamer"). These projects are usually made to scare/surprise people or to make a person laugh. Screamers can be fun and enjoyable, but they should not be too distressful or otherwise inappropriate as Scratch is an all-ages website."[1]