I've been finding a stuck-glitch that happens a lot: if you fall between two objects that are near each other, you get stuck into an infinite falling glitch and get stuck. Examples include the railing top of a signpost, certain small objects, the chimney stack near the power generators at the top of the namechange building, etc.
I think you could fix it "everywhere" by: if the player is still falling after a long time (say, 2 seconds of falling, more than enough to fall from the tallest building to the ground), just automatically let them be able to jump again once. Most of time, being able to jump out is enough to escape the small places you can get glitched/stuck in.