Floatingbox with Chinese character blank linebreak

Hello, FLoatingbox with textfragment When inserting text with Chinese characters, spaces are automatically converted to newlines. However, spaces in English are normal. May I ask what is going on? Is there a corresponding API that prohibits the conversion of spaces into newlines?
This is my complete test code, if the font is not suitable, you don’t need to set it.AddImageStampAsBackgroundInFloatingBox.zip (122.2 KB)

Thank you very much, looking forward to your reply.

@hewei

We have logged this problem in our issue tracking system as PDFJAVA-42376. You will be notified via this forum thread once this issue is resolved.

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