Dead players can traverse dimensions

The Bug:

Dead players can traverse dimensions.

Steps to Reproduce:

1. Construct and open an end portal.
2. Fly up high directly above it and run "/kill" as you're falling so that you enter the end portal whilst on the death screen.
3. Take note as to whether or not dead players can traverse dimensions.

Observed Behavior:

Dead players can traverse dimensions.

Expected Behavior:

Dead players would not be able to traverse dimensions.