Good morning,
I saw that problem in creative mode, survival mode and in each server. When you're crouched you can't change the item in your hand. It could be useful to add that possibility (if it's not a bug, of course). That problem I got on my Mac, so maybe it's a problem connected with it, I don't know.
Thank you for this opportunity to help.
IuriJazz
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@violine1101 Thank you so much. I tried to search it, but i didn't saw it. Sorry for that.
Thank you for your report!
We're actually already tracking this issue in MC-121772, so I resolved and linked this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
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.