Make a new supertrope with a new name for "a bed or chair with moving parts that works wrong, trapping, injuring or killing the person in it." Hard split Murphys Bed out to specifically cover Murphy Beds (beds that fold into the wall or a cabinet); hard split other types as they gain enough examples.

Split out serious uses (someone is or has been actually injured or killed) from comedic uses under a name like Killer Furniture, keep Murphys Bed for comedy uses; deal with variants based on the type of bed or chair on a case by case basis.

Make Murphys Bed into a supertrope for all types of bed and folding-chair related mishaps; Hard split out each type (wall-bed, sofa bed, folding bed/camp cot, bunkbed, hammock, smart bed, and lawn chair) into its own trope as it gets enough example.