Vulkan causes FPS drop and stuttering vs OpenGL on AMD GPU (RX 9060 XT)

Short description:
Using the Vulkan rendering backend causes a significant performance regression
compared to OpenGL on AMD GPUs. FPS drops drastically and persistent stuttering
occurs even at lower render distances.

Steps to reproduce:

1. Launch Minecraft 26.2 Snapshot 7 with the Vulkan rendering backend enabled
   (Video Settings → Graphics API → Prefer Vulkan)

2. Load a new or existing world

3. Set render distance to 32 chunks and observe FPS and stuttering

4. Change render distance to 16 chunks and observe FPS and stuttering

5. Switch the Graphics API to Prefer OpenGL, restart the game

6. Repeat steps 2–4 with OpenGL and compare

Expected result:
Vulkan should perform similarly or better than OpenGL, as AMD GPUs are designed
to take advantage of low-overhead APIs like Vulkan.

Actual result:
With Vulkan:

• 32 chunks: ~90 FPS with heavy and persistent stuttering

• 16 chunks: ~220 FPS but with constant stuttering

With OpenGL:

• 32 chunks: 230+ FPS with no stuttering

• 16 chunks: 490+ FPS with no stuttering

The stuttering occurs continuously, not just during initial chunk loading,
suggesting possible shader recompilation issues or suboptimal Vulkan driver
integration for AMD on Windows.