Michael Trew explained on 5/2/2022 :
AIUI, Bob isn't asking about "reference", but about the first time a
toilet was in view on camera, and being an item in the background would
I'm not sure what shows were filmed "on location" during the '50s, and
a toilet in the background for other shows would require the set
builders to build a bathroom (or a plumbing showroom), and I can't
recall much of that (admittedly, I can't recall much of the shows I
recall, which is the short list of Donna Reed, Father Knows Best, Leave
It To Beaver, and My Three Sons; I think kitchen scenes dominated).
Rule #0: Don't be on fire.
In case of fire, exit the building before tweeting about it.
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