The ad on the right side is part of the built‑in advertising space in Microsoft Casual Games such as Microsoft Mahjong. These games reserve specific areas of the screen (for example, the right side of menu, gameplay, or daily challenge screens) for display ads, and that space is not removable from within the game.
Shrinking or resizing the game window so that the playable area fits comfortably beside or around the ad is the only behavior described in the available information. There is no documented in‑game setting to disable or move that ad area.
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