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.

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.

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.