Warning "Invalid glyph found, continuing..." when exporting flowed text with line breaks
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#### Summary:
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Inkscape version: 1.2.2
OS version: Windows10
#### Steps to reproduce:
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- open Inkscape and create an empty file
- click "Text" button, and draw a sufficiently large area.
- 
- Input any texts with any font, (For example: "aaaaaa") and press "Enter" to create a new Line
- 
- Input any texts with any font. (Can same as first line or diffrence)
- Save the file with any filename. (For example: "绘图1.svg")
- Use inkscpae command to covert the svg file to pdf.
- inkscape --export-area-drawing --export-filename=bin\绘图1.pdf src\绘图1.svg
- 
#### What happened?
Error message: "Invalid glyph found, continuing.." show in the console.
#### What should have happened?
Conert svg to pdf successfully without any error or warning.
Sample attachments:
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#### Version info
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issue