If you walk out onto the balcony from the spawn, you can jump onto the frames of the giant glass windows on the blue building you're on, because the glass is cancollide false.
Continue going down this window (https://prnt.sc/qmesi0) and around the corner and you can reach the fire escape ladder from slightly later in the game.
Based on the current glitchless record, it would cut about or just under 2 minutes off of his run.
Note: Once you do this glitch, you will no longer trigger checkpoints and when you die you'll go back to the beginning of the game.
This has been found before this game was on sr.com
I was going to do a run trying to do this because I tried doing this the first time I ever played this obby, but I'm not sure if I want to spend time on that