Deleting candidate CJK words in IME also deletes text already entered

I can reproduce the issue in a vanilla environment, so I recreate the issue.
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When I delete candidate CJK words in IME, Minecraft also handles the backspace event, causing text already entered to be deleted as well

Developers of fcitx said that this should be fixed on Minecraft's side.

github

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当我删除中文候选词时,已经输入的字被删除

fcitx的开发者表示这是mc的问题