If you throw a potion on ground and open the GUI before it lands and gives you the effect, it won't be shown.
MC-169882
Potion effects aren't shown in gui until you reopen it
Resolved
Duplicate
0
Thank you for your report!
We're actually already tracking this issue in MC-267, so I resolved and linked this ticket as a duplicate.
However, that ticket has already been resolved. That means that this is not considered a bug and won't be fixed. Please do not leave a comment on the linked ticket.
If you haven't already, you might like to make use of the search feature in the future to see if the issue has already been reported.
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