NTSC-JP. Spoiler: Note 1: The pixel aspect ratio of a 3440x1440 display is 2.3888888. The pixel aspect ratio of a 2560x1080 display is 2.3703704. This is the reason why there are two 21:9 codes. Note 2: Make sure to download the newest dolphin build. Note 3: While most games do work with the Aspect Ratio set to "Auto", some games might require ... More @Wikipedia
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