Clicking on it will open the backpack. Thank you for the feedback. We will try to address this issue so it will be more clear in a future update.
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The gittering is happening anytime I rest the cursor at the top of the screen, I don't click and it gitters. If I click the inventory opens for a second and immediately closes. https://www.youtube.com/watch?v=zr39Om4fxCI&ab_channel=shortjustin