Affects Version/s: 1.15.2
Fix Version/s: None
Environment:Operating system: Windows 10 - 64 bit.
Minecraft Java Edition - Version: Release 1.15.2
Java version: Java 1.8.0_51 64 bit
Allocated RAM: 2GB out of 8GB
CPU: 8x Intel(R) Core(TM) i7-4770 CPUT @ 3.4 GHz
GPU: GeForce GTX 1060 6GB/PCIe/SSE2
While falling, when you land between a solid block and a Redstone repeater, you will not take damage if you jumped before you started falling, however, you just walk off a platform without jumping, and land between a solid block and a Redstone repeater, you will take fall damage.
1. Place a Redstone repeater
2. Two blocks above it, place any other solid block like stone
3. Build a platform high up, climb on it, switch to survival mode, make sure "fallDamage" gamerule is set to "true"
4. Jump from the platform (don't wall off, jump) and land between the Redstone repeater and the block you placed above it
I have tested this on Minecraft version 1.8.9, but the bug did not reproduce there. I have not tested if this bug works with other blocks other than Redstone repeater, this bug I discovered by accident while I was falling next to a wall. I have also made a recording showing in detail how to reproduce this bug which was recorded in a newly created world. Since the maximum file size for attaching files is 10mb, and the recording file size is bigger than 10mb, I have uploaded the video on YouTube (https://www.youtube.com/watch?v=fZaC1N-4I7s).
After trying to reproduce the bug once more, I have noticed that for whatever reason, this bug does not reproduce every single time. Perhaps there is something else that is triggering this bug.