element doesn't exist on type TestContext about ember-test-helpers

[eugenioenko]

I see, thank you for the clarification and the provided solutions, really appreciated 👍

[chriskrycho]

That's correct! The main TestContext doesn’t have that on it, so this was a deeply unsafe type which could (and did) lead people astray. See the ember-qunit v6.1 migration guide for a discussion of a few options here, including explicitly specifying the (unsafe, but at least safer!) this: RenderingTestContext parameter and switching to qunit-dom—the latter being the recommended path. (There's a very useful codemod to convert your tests to using qunit-dom; we ran it across the millions of lines of tests for LinkedIn.com a few years ago and haven't looked back!)