After the recent change to the way RTX resources are handled in beta 1.18.20.25/preview 1.18.20.26:

• Fixed a case where ray tracing resources would be destroyed prematurely on level exit from an RTX-enabled world

The game will either completely crash or the rendering engine will, causing it to switch to using DirectX 11 instead of DirectX 12. This results in completely disabling DXR, and users have to restart the application to fix it.

Steps to Reproduce:

1. Apply an RTX resource pack to global resources in settings
2. Open a world with RTX on
3. Quit the world

Observed Results:

The game will either crash and close the application or a red screen will flash and the rendering engine will subsequently switch to DX11, disabling DXR from running when entering any other world or server.

Expected Results:

The world should be closed properly, without causing any crashes or switching the rendering engine to DX11. This full functionality was present before beta 1.18.20.25. 

My computer's specifications, if this issue isn't reproducible on higher end devices: 

CPU: Ryzen 5 2600
GPU: GeForce RTX 2060
RAM: 16GB 3000MHz
Storage: 128GB M.2 SSD

Link to the RTX resource pack in use when testing the bug:
https://www.mediafire.com/file/7rm4nmgtr57o2ys/Defined_PBR_1.1.7.mcpack/file