Introduction
When working with MetaMask APIs, you might encounter this warning: “Property ’ethereum’ does not exist on type ‘Window & typeof globalThis’.ts(2339)” when accessing window.ethereum
in a TypeScript project. MetaMask injects a global API into websites visited by its users at window.ethereum
![a code snippet screenshot](/static/img/error-ethereum-does-not-exist.png)
To fix this warning, and corresponding compile error, add this declaration at the top level of your file, after imports.
declare var window: any
Note, this is not the best fix as this temporarily fixes the warning by telling the TypeScript
compiler to treat window
as of type any
hence ignore any warnings.
This sacrifices also any IntelliSense and auto-completion provided by code editor on the window
object.