Browser play has visual, performance or input problems
Kenney recommends the downloadable version when the browser build has these problems. The official download section offers Windows and Linux builds. Open the official game page and choose Download Now; this guide does not mirror the files.
The downloaded game still runs poorly
Try changing visual quality through the in-game options, as recommended by the developer. This is a troubleshooting step, not a promised performance fix.
macOS
The developer marks macOS unsupported. A browser being available on a device does not mean this game is supported there.
An unfamiliar button prompt
Use the Controls page to translate controller icons into keyboard actions. The developer also documents a Chrome gamepad flag workaround on the official page; check that current instruction there because browser flags can change.
Report an unresolved issue
Record your operating system, browser or downloaded build, the action that fails, and any error message. Send that context through the developer’s own support/comment page. This site has no access to your game save.