Some (but not all) item frames in worlds upgrade from previous versions do not render their items correctly - some do not appear to render the item at all, where others only seem to render it at a certain distance/angle, and block items also get certain faces occluded at random. From my testing, this does not appear to affect new worlds, or worlds that did not have item frames before 25w41a, but does affect new item frames placed in an upgraded world that already had item frames. Which item frames render incorrectly appears to change upon reloading the save.
Attachments: First image is in version 1.21.10, second image is the same set of item frames after upgrading to 25w41a. Third image are new item frames placed in the same world.
Environment
Windows 10
Java 21.0.7
NVIDIA GeForce RTX 2070
OpenGL 3.3.0
NVIDIA 576.52
this is happening to me too