Photoshop can't import stacked photos (MP4 files) from Panasonic Lumix G9

My latest photoshop version can't import stacked photos (MP4 format) from a Lumix G9. I already tried to convert the file to different formats. still the same issue. Seems to be a bug in Photoshop 2020 on macOS Catalania 10.15.4. So I'm using latest version for everything (camera firmware, photoshop and macOS).

The MP4 file is attached.

Thanks for your support.