Normal minecarts shake and cannot be ridden on active powered/activator rails (1.26.30)

Hi Mojang Team,

I've encountered a very specific bug regarding minecart physics/behavior right after updating to version 1.26.30.

Standard (normal) minecarts completely refuse to function or move on Powered Rails and Activator Rails. There are absolutely no blocks obstructing the path, and I've even tried testing it out in the wide-open ocean space, but it still doesn't work.

Furthermore, when the minecart is placed on an active Powered or Activator Rail, it glitches out and shakes violently as if it is constantly being hit/struck. Because of this glitch, players are completely unable to ride or mount the minecart while it is on these active rails.

Here are the crucial details regarding this bug:

1. It ONLY happens in pre-existing survival worlds created before the 1.26.30 update.

2. If I create a brand new world, the bug does not occur, and everything works 100% perfectly.

3. Hopper minecarts and Chest minecarts work completely fine without any issues, even in the bugged world. The glitch is strictly isolated to standard minecarts on powered/activator rails.

4. I also exported this world map and tested it on Minecraft Pocket Edition (MCPE) on a completely different device, but the exact same bug still persists there, confirming it's an issue embedded within the world's data.

I have attached a video file named "Minecraft 2026.06.17 - 16.54.44.01.mp4" to show the exact bug happening in real-time.

Steps to Reproduce:

1. Load a world that was created prior to the 1.26.30 update.

2. Place down a Powered Rail or Activator Rail and power it up with a Redstone Torch.

3. Place a standard/normal minecart on top of it.

4. Observe that the minecart is glitched and fails to respond to the rail.

Observed Results:
The standard minecart glitches out, shakes as if it's being hit repeatedly, and completely ignores the rail's functions. Additionally, the minecart cannot be ridden or mounted by the player at all while on these active rails.

Expected Results:
The standard minecart should move smoothly on powered rails, identical to how chest/hopper minecarts behave, and how it normally works in newly generated worlds.