In the 1.9 Snapshots, when you ride a minecart, the chunks would not load. This could cause serious problems, as you cannot leave the minecart if you go into unloaded chunks.

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I thought that the minecart ride was going to be normal:
Describe what you thought should happen here

The chunks wouldn't load and I got stuck in the minecart with loud noise
Describe what happened here

Steps to Reproduce:
1. Ride a minecart
2. make the rail go multiple chunks
3. Make the minecart accelerate