If you have two items in your inventory, select the item that you don't want to disappear, then very quickly (as in pretty much instantly) press the number of the item in the hotbar that you want to disappear, as well as Q (or the drop item button).
For example:
I have steak and a sword in my inventory.
The steak is in slot 2, and the sword in 1.
if I hover over 2, and press 1 and q at the same time, the steak will be thrown, and the sword will disappear out of the inventory, until it is clicked in the inventory screen, or thrown as well.
Thank you for your report!
However, this issue is Invalid.
Your game, launcher or server is modified.
If you can reproduce the issue in a vanilla environment, please recreate the issue.
Any non-standard client/server/launcher build needs to be taken up with the appropriate team, not Mojang.
Any plugin issues need to be addressed to the creator of the plugin or resource pack.
If you have problems on large servers, such as The Hive and Hypixel, please contact them first as they run modified server software.
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