A-Button held down glitches

The hidden characters glitch is a very simple natural glitch in Pokémon Red, Blue, and Yellow.

The player simply needs to save their game, and have the A button held when the "[PLAYER] saved the game !" text box disappears.

The text box and save menu will close, but not the START menu. Thus, the characters hidden by the save menu won't reappear until the player releases the A button.