I don’t know if there is a better way to ask this. But, I mean to open the small down arrow which shows the list of tabs (see following) using a keyboard shortcut

Sign Up to our social questions and Answers Engine to ask questions, answer people’s questions, and connect with other people.
Login to our social questions & Answers Engine to ask questions answer people’s questions & connect with other people.
Lost your password? Please enter your email address. You will receive a link and will create a new password via email.
Please briefly explain why you feel this question should be reported.
Please briefly explain why you feel this answer should be reported.
Please briefly explain why you feel this user should be reported.
The Command that you are looking for is
Window.ShowEzMDIFileList, it can be accessed(at least on my machine) by Ctrl + Alt + Down Arrow