No prompt for setting up a master password

Hi all, 

Hope you're well. I'm a new user and was trying to set pgAdmin up for the first time. All of the instructions and tutorials and other resources I can find outline how there should be a prompt for setting up a master password when you first open. This did not appear for me. I tried deleting, redownloading, and opening again and it still doesn't appear. When opening the program after download, it also doesn't ask for a password (only when trying to connect to a server). If it's helpful to know, I'm using Mac OS.

Is there a way to set the master password without having the prompt appear? If yes, where/how? If not, what might you recommend for this situation?

Thank you in advance.

Stephanie