open new compose window, add some recipients you used in previous emails and wait for suggestion (unfortunately I don't know the exact way to force suggestions - most likely if you frequently send emails to the same three contacts, when you add two in the new compose, Gmail will suggest third)
Steps to reproduce:
gmail.dom.composes()[0].recipients()
Expected result:
Actual result:![image](https://user-images.githubusercontent.com/1419318/182607781-7eca084f-4e66-4d5b-ba8c-34e86953509c.png)