.qtbridge using Group in Figma yields Metadata format error when imported to QDS

Here's the QDS version I use.

I attached the project for reproducing the issue.

There, you can find .fig files and .qtbridge files.
group.qtbridge yields an error but frame.qtbridge doesn't.

The difference between frame.qtbridge and group.qtbridge is literally just whether group being used or frame being used. 
You can verify that by opening .fig files.

Once group.qtbridge file is imported, this error shows.

Unable to find Artboards.
C:/Users/81808/AppData/Local/Temp/QtDesignStudio-NHmIlp/Untitled.metadata
Parsing failed. Metadata format error.
C:/Users/81808/AppData/Local/Temp/QtDesignStudio-NHmIlp/Untitled.metadata
No components to write.
Import done.