This game was exported in Flash and, as you probably know, Flash has been discontinued. As such, I can only provide access to the source code and the .swf file at the moment.
If you happen to have an ancient computer that still runs Flash in the browser, or a copy of the Adobe Flash Standalone Player, you should be able to run the game.
At some point I may port the game to JavaScript or similar, and it’s possible that the ruffle Flash emulator will get to a point where this game will run again. Let’s see.
Two Player Breakout was written in ActionScript 3 using Adobe’s FlashBuilder 4.5 and the excellent Flixel library. It was made in a couple of hours and is based on Breakout code from Photon Storm and uses the same colour choices. It uses sound effects made in bfxr. The font in Two Player Breakout is Commodore 64 Pixelized by Devin Cook.
You can read my writing about the game on my blog.