Minecraft Dev Launcher Start Crash

When I select the Snapshot 13w16b and click Play, a crash report shows up.

What I expected to happen was...:
Minecraft starts normal with the Snapshot.

What actually happened was...:
Minecraft Dev Launcher opened a new "tab" and showed me the crash, crash file attached.

Steps to Reproduce:
1. Open Dev Launcher
2. Select Snapshot 13w16b
3. Click Play