Huh... I was chatting with "Mixtral 8x7B" (AI) courtesy of DuckDuckGo ("Chat" tab while search results are being displayed), and for kicks asked "What is the midnight pub?", which led to:
> The Midnight Pub is a fictional location that appears in > the Harry Potter series of books by J.K. Rowling. It is a > pub located in the Hog's Head Inn, which is a tavern in the > village of Hogsmeade, near Hogwarts School of Witchcraft > and Wizardry. > > The Midnight Pub is a secret meeting place for members of > the Order of the Phoenix, a secret organization founded > by Albus Dumbledore to fight against the dark wizard > Voldemort. The pub is hidden behind a concealed door in > the Hog's Head Inn, and it is accessible only to members > of the Order. > > The Midnight Pub is a small, dimly lit room with a bar > and a few tables. It is a place where members of the > Order can gather to discuss their plans and strategies > in private. It is also a place where they can relax and > socialize with each other, away from the dangers and > stresses of their mission. > > The Midnight Pub plays a significant role in the Harry > Potter series, as it is the site of several important > meetings and discussions. It is a symbol of the camaraderie > and solidarity of the Order, and it represents their > commitment to fighting against the forces of darkness.
I honestly had no idea!