Using 2 piston face and above rail causing creating fake diagonal rail

I am using to redstone reader, but using 2 piston and 3 rail create makes fake diagional rail.

Step to reproduce:

1. Create 2 pistons, but 1 piston facing and more piston is above and 1 under the block is facing to block
2. Place redstone 2 piston and lever
3. Press the lever, and try again even making fake diagonal rail

Warning: Affected in java edition.