In order to open the plugin with multiple products, you need to click on the drop-down list in the top of the plugin:
Under "New Accounts" the "Add..." button can be found. Press on it, and it will open a new login window. There you can insert the credentials for the other product you are using!
Important: To be able to log into both products you will need to have different passwords on each platform
Note: You can be logged in to the multi-product plugin on one device only!