Can't browse subfolders on FTP servers that don't support MLST command in vlc-android
From what I can tell, the FTP accessor in VLC will fallback to using the NLST command when MLST is not supported by the server. This command doesn't return any further information other than the filenames, so the accessor will initially mark all media as "unknown" type when discovering files in the server, and down the line they will be resolved as "file" type (I think it goes through vlc_readdir_helper_additem -> input_item_NewExt -> input_item_SetURI -> GuessType
).
libvlc will return a media list where all directories have "file" type only and android-vlc will show them as such when navigating into the server, making it impossible to continue navigating into subfolders.
I see this issue on version 3.3.4 for smartphones and TV and I could also reproduce this issue on master branch. I haven't tested with a server that does support MLST, but I suspect it works fine.