Custom size is not applied in "empty" TextRun

[quentin-ineat-ca]

Hello,
Thank you for the library.

I use default style at top like :
styles: { default: { document: { run: { size: 20, }, }, }, },

I use the classical to make an empty line (I know it could be shorter but for the example).
return new Paragraph({ children: [new TextRun({ text: "" })], });
But using the following, the size is not override and staying at the default 20. If text not empty, it's working fine with the correct 40 size.
return new Paragraph({ children: [new TextRun({ text: "", size: 40 })], });

In Word, it's possible to increase the font of an empty line. Is it a bug or I do it wrong ?
Thank you !