MuseScore 4 files dissapearing on copy and paste in Linux/Chromebook

I have Linux terminal installed, running MusScore 4 (current) (with FUSE2). When I try to copy my files from the Linux folder to an SD card, USB stick or Google Drive, the entire Linux folder disappears. I know the files are there because I can open them in MuseScore. Closing the linux container resolves the issue and I am able to see the files again. I'm on a Samsung Chromebook, 64GB/4 GB RAM. Everything else is running smoothly. Also once the container has repoened I am able to copy again, but just once and then the same problems occurs. The error I get is Directory not Usable.
OK so here's a strange thing. If I shut down the linux terminal I am able to see the MuseScore files in my Linux folder. If I try to copy them to sd card or stick I get a copy operation failed. But I can copy them to my Chrome downloads folder.

Any help greatly appreciated. I posted this on Chrome but they suggested I ask here. https://support.google.com/chromebook/thread/271479194/linux-files-disa…
Thank you