What steps will reproduce the problem?
1. Install WaaaghBar_Menu
2. Disable the EA_Mythic Main Menu Window

What is the expected output? (without the mod, using default main menu)

1. When you open the banker or a merchant your backpack automatically opens along side it.
2. Regardless of how the backpack is opened, you can close the backpack via the little x button in the top right corner.

What do you see instead? (using mod, disabled main menu)

1. When you open the banker or a merchant your backpack does not open automatically, you need to manually open it using the button on the menu.
2. Regardless of how the backpack is opened, you can *not* close the backpack via the little x button in the top right corner. You must use the button on Waaaghbar_Menu to close it.

What version of the product are you using?

The latest

Do you have an error log of what happened?

No

Please provide any additional information below.

I believe that the MainMenuWindow addon that is default, has some sort of code related directly to the backpack. Only with this enabled will the backpack function properly. Other than that, the only thing I can think of is that the built in main menu uses a different API than 3rd party mods.