I can't report the bug in Korean, so I send it again.
1. Select Quick Slot 9.
2. Open the chat window.
3. Press the chat bar.
4. If you were holding something in Quick Slot 9, it would have disappeared or changed to something else.
5. If you leave the chat window right away, you will find that you are choosing Quick Slot 8.
There is a possibility of mistranslation using a translator.
a summary
1.Select Quick Slot9
2. Chatting
3. I was choosing Quick Slot 8.
Photographs cannot be shown as unknown technical causes.
Thank you for your report!
However, this issue is a Duplicate of MCPE-49117.
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