Silence backups are always invisible with MTP
Both kind of backups (Plaintext and Encrypted) have always been impossible to see and copy from MTP mountpoints, and can only be listed through
adb, and pulled with
adb. This is much less handy than being able to copy it from your usual file manager, and I see no reason that would explain it to not be visible (enabling the display of hidden files doesn't show them either).
Properties seems to be the same as other directories created by the system and visible through MTP:
drwxrwx--x root sdcard_rw 2019-11-27 21:17 Pictures drwxrwx--x root sdcard_rw 2020-01-08 18:38 Podcasts drwxrwx--x root sdcard_rw 2016-06-28 05:15 Ringtones drwxrwx--x root sdcard_rw 2020-08-16 10:56 SilenceExport -rw-rw---- root sdcard_rw 2166974 2020-08-16 10:56 SilencePlaintextBackup.xml drwxrwx--x root sdcard_rw 2019-03-15 05:02 System
EDIT: This could be a more general problem with some datas written by applications as I did backups from Two factors applications too that seems to suffer from the same issue.