Mupen64Plus Glide64MK2 Edit Resolution/Controls

[rastaman1201]

Hi,

I am running Recalbox 8 Electron fro PC and I am trying to get into Mupen64Plus Glide64MK2 to change the screen resolution and controls but the Hotkey key + B button is not letting me into RetroArc like the other emulators do...? No other button combination does either. Is this a RetroArc Core or independent emulator? How do I get into this emulator?

Thanks