Solution: Property 'then' not found

This was a frustratingly easy fix once I knew what it was. However, I could not find a simple answer based on the error text. Here it is so that you do not have to search the entire internet to find it when you hit this error in Playwright.

Make sure that your expect call has an assertion (I.e .toBeVisible()). If you're writing a lot of tests at once this Is an easy one to miss.