I recently did a fresh installation of Fedora33/Mate, kernel is 5.9.16-200.fc33.x86_64. Actually none of my android devices can be accessed via USB and mtp, although I have installed mtpfs, jmtpfs, simple-mtpfs. Simple-mtpfs recognized my devices, but does not display any folders:
[jojo@localhost-live ~]$ simple-mtpfs -l
1: SamsungGalaxy models (MTP)
[jojo@localhost-live ~]$ simple-mtpfs --device 1 FOLDER
[jojo@localhost-live ~]$ ls FOLDER
ls: cannot access ‘FOLDER’: No such file or directory
Trying to access via file manager by clicking the mtp icon is just looping, no matter if I you caja, nautilus, PCManFM or 4Pane. Have not had any trouble with mtp in Fedora32.
FWIW, my experience with such GIO mounts in a standard (maybe Mate is different) Fedora 33 virtualbox guest is:
They don’t automount; you need explicitly to mount them with the system file manager.
They are mounted in the usual place: /run/user/1000/gvfs/
4Pane only supports GIO mounts in the recently-released 7.0; you’re probably using 6.0. Also it only detects and displays the data, it doesn’t mount them.
At my system they are automounted. The error box occurs after the device is mounted. After I quit the error box with ‘OK’ I see the mounted device in my file manager. But trying to open the device’s location results in a never ending sandbox, no matter which file manager I use.
I did some further testing.
The devices open in ‘Android File Transfer (MTP)’, so this is the good news.
But trying to open in any file manager causes the file manager to be stucked, no matter if I use caja or 4pane or PCManFM.
After having checked mainly in the area of gvfs, mtp and libmtp I recognized that my issue might be related to USB3. After having connected my devices to USB2 it works as expected.