In survival I took a Mob through a Nether portal on a lead.
The mob went through first and I followed.
Upon entering the Nether the lead came off the mob and went back through the portal.
I went back to the overworld to retrieve the lead and found two leads instead of one.
After further testing I concluded that this glitch works nearly every time with all mobs (that leads work on).
This glitch works in both single player and multiplayer modes.
Environment
Windows 7
Thank you for your report.
However, your ticket has been resolved as a duplicate.
This issue has been linked to the original bugreport: MC-15270. You can find or add further information on that report.
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