TCM's version opened with text describing the missing ending, "which Keaton said produced the greatest laugh of anything he ever did." After describing the ending, it said, "Alas, most of this gag is missing and may never be found." It went on to say that about 3 minutes were missing.
Compared to the YouTube version linked above, the TCM version was missing some of the beginning -- the very first shot was Keaton dusting off the man exiting the car. There were a few brief gaps as he jumps in front of the streetcar, and possibly elsewhere.
It ended with Buster on the verge of jumping off the diving board, mentioned the missing ending again, showed a reaction shot of the girl and the group rushing to peer into the hole, said "Years later ..." and showed a still of Buster with his Chinese wife and kids. The title cards also varied (for example, the meeting was about acquiring an armadillo!). Of course, I don't know which were more authentic.
The TCM version was by Brownlow and Gill, who always did great work, and had a copyright date of 1987. That was followed by another: "Special contents of this edition (c)2011 Douris UK Ltd."
It's too bad that they're showing an incomplete version when the complete (?) one exists. But at least it introduced me to this great movie.
I don't get it. I have the Kino blu-ray and like some mentioned above it clearly states the diving scene has never been found. There's even a virtual essay on the disc about it never being found. And then I find out it's available on youtube?