To offload some media files from my phone, I connected it to my (Linux) PC through USB, and set it to file transfer mode (MTP) so that the internal storage gets mounted. I see many files, which I can copy without a problem, but there are also many files that I don't see at all on my PC.
Exploring the file system with "adb shell", there turn out to be many more files in the same file system.
Does anyone know why they don't show up and what I can do about it? The file permissions seem to be the same as those of the visible files.