Rendering my GuiContainer alongside the inventory?

[TLHPoE]

I've figured out a way to detect when the player's inventory is open, but is it possible to render another GuiContainer on the side of the inventory?

[Mazetar]

Which forge version are you using?

Assuming it's one of the latest versions there is events added for opening GUI's.

You should be able to find it in the same place as the other client events are located

 

With that you could make sure to do the actions you need in order to render your own gui stuff on top of it.

Or you could prevent the player from opening the vanilla inventory and instead open your own version of it.