Rinsma explained that it’s already “relatively well-known” that PDFs can support a number of features such as dynamic content scripting when opened in something like Adobe Acrobat/Reader. Some of that same scripting support, however, is also available in both Mozilla Firefox and Google Chromium ’s respective PDF readers, PDF.js and PDFium.

A security analyst created a playable version of Tetris that lives within a PDF file. Gameplay is a janky, but the project shows a unique way to use inputs and outputs within a PDF file.

However, modern browsers can unlock more features for PDF documents, as proven by new ports of Tetris and DOOM. Thomas Rinsma, a security analysist and developer, published a working demonstration of the classic puzzle game Tetris running entirely in a PDF.