Not so common in the west, but quite a few Japanese systems like PC98, X68000, and even later consoles like Sega Saturn had some games that were in 240p or 480p that were meant to be viewed on a 4:3 display but letterboxed for a widescreen look.
In the early days this was done by manually lowering the display's vertical screen size until it looked correct. In later years most 4:3 TVs sold in Japan have a button on the remote to switch to letterbox mode.
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