A while back (a year or so ago), I was in a subway car in New York, and saw this brilliant replacement of the “Do not lean on door” sticker
On Saturday night, I was on the subway with some friends who were visiting me in New York. We were talking about the silliness of all the signs in the subway, and I mentioned the above sticker, and low and behold one of my friends turns around and says “Like this one?” - Wow! It wasn’t the exact same one (the one above was on the left door, the one on Saturday was on the right door) but wow! For future reference, this sticker can be found on the L, in car 8165, on door R8.
For reference, the normal subway doors look like this: