Falling Blocks break when block underneath is pulled horizontally by retracting sticky piston

When a Gravity affected block is sitting on top of a normal block and a piston retracts that normal block then the gravity affect block above gets broken. Here’s a video of it happening; https://drive.google.com/file/d/1S6j-LMl8JD5PWoEAjvPG1-0h5ZRnmBPH/view?usp=drivesdk