Inventory opening is detected while in Nether Portal

The bug

When tutorial asks you to open your inventory, while you're in the nether portal waiting to be teleported, if you press E to bring up the inventory, you complete this tutorial even though the inventory itself cannot appear while you're in a nether portal.

How to reproduce

1. Edit options.txt so it has tutorialStep:open_inventory in it
2. Open/create a world in creative, make sure you have a lit nether portal
3. Switch to survival, walk/jump/break blocks to make tutorial notification ("Open your inventory") appear
4. Walk into the portal and press E
   →Tutorial notification will be removed, while inventory hasn't appeared