THIS IS ALL IN 1.21.11 SINGLE PLAYER I HAVE NOT TESTED IT IN OTHER VERSIONS OR MULTIPLAYER. I DO USE SOME MODS SO IT MIGHT BE BECAUSE OF THAT.
If you are in an item slot and click another slot hotkey and drop key, it drops the item you are holding and when you pick it up, you don't get and item and you have to click where the item is in your inventory to see it.
Example: In your 1st item slot you have a sword and in your 2nd you have an axe. You are holding the axe (2nd slot). you press 1 and Q at the same tick. It will look like you dropped an axe and you will lose your sword. when you pick the axe on the ground, nithing changes in your inventory. when you press E and click on the 1st item slot with your cursor, You will see that you picked the sword with your cursor.
Thank you for your report!
We are tracking this issue in MC-154881, so this ticket is being resolved and linked as a duplicate.
If you would like to add a vote or provide any additional information to the main ticket, it would be appreciated.
Additionally, your game is modified. Please only report issues that you have verified to be present in a vanilla environment, and make use of the search feature to see whether an issue has already been reported.
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