ive opened and logged into minecraft. now i want to play the demo to see if it plays on my computer, and buy it. whenever i click play demo, it brings up the game with white and mojang. then that closes and the launcher comes back up with game(output)

Put the summary of the bug you're having here

What I expected to happen was...:
Describe what you thought should happen here
the demo to open, so i can make sure my laptop can run it
What actually happened was...:
Describe what happened here
the game says not responding when clicked on, then brings me back to launcher

Steps to Reproduce:
1. Put a step by step guide on how to trigger the bug here
2. ...
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