Things that do work:
- moving from local drive to protondrive
rclone moveto test_file.bak proton:test_file.bak -vv
2025/01/03 14:13:23 DEBUG : rclone: Version "v1.68.2" starting with parameters ["rclone" "moveto" "test_file.bak" "proton:test_file.bak" "-vv"]
2025/01/03 14:13:23 DEBUG : Creating backend with remote "test_file.bak"
2025/01/03 14:13:23 DEBUG : Using config file from "/home/niels/.config/rclone/rclone.conf"
2025/01/03 14:13:23 DEBUG : fs cache: adding new entry for parent of "test_file.bak", "/home/niels/drive"
2025/01/03 14:13:23 DEBUG : Creating backend with remote "proton:"
2025/01/03 14:13:23 DEBUG : proton drive root link ID '': Has cached credentials
2025/01/03 14:13:26 DEBUG : proton drive root link ID '': Used cached credential to initialize the ProtonDrive API
2025/01/03 14:13:26 DEBUG : test_file.bak: Need to transfer - File not found at Destination
2025/01/03 14:13:28 DEBUG : test_file.bak: sha1 = 4e1243bd22c66e76c2ba9eddc1f91394e57f9f83 OK
2025/01/03 14:13:28 INFO : test_file.bak: Copied (new)
2025/01/03 14:13:28 INFO : test_file.bak: Deleted
2025/01/03 14:13:28 INFO :
Transferred: 5 B / 5 B, 100%, 5 B/s, ETA 0s
Checks: 1 / 1, 100%
Deleted: 1 (files), 0 (dirs), 5 B (freed)
Renamed: 1
Transferred: 1 / 1, 100%
Elapsed time: 4.2s
2025/01/03 14:13:28 DEBUG : 8 go routines active
- copying from protondrive to protondrive
rclone copyto proton:drive/test_file.bak proton:backup/test_file.bak -vv
2025/01/03 13:55:55 DEBUG : rclone: Version "v1.68.2" starting with parameters ["rclone" "copyto" "proton:drive/test_file.bak" "proton:backup/test_file.bak" "-vv"]
2025/01/03 13:55:55 DEBUG : Creating backend with remote "proton:drive/test_file.bak"
2025/01/03 13:55:55 DEBUG : Using config file from "/home/niels/.config/rclone/rclone.conf"
2025/01/03 13:55:55 DEBUG : proton drive root link ID 'drive/test_file.bak': Has cached credentials
2025/01/03 13:55:57 DEBUG : proton drive root link ID 'drive/test_file.bak': Used cached credential to initialize the ProtonDrive API
2025/01/03 13:55:59 DEBUG : fs cache: adding new entry for parent of "proton:drive/test_file.bak", "proton:drive"
2025/01/03 13:55:59 DEBUG : Creating backend with remote "proton:backup/"
2025/01/03 13:55:59 DEBUG : proton drive root link ID 'backup': Has cached credentials
2025/01/03 13:56:01 DEBUG : proton drive root link ID 'backup': Used cached credential to initialize the ProtonDrive API
2025/01/03 13:56:01 DEBUG : fs cache: renaming cache item "proton:backup/" to be canonical "proton:backup"
2025/01/03 13:56:02 DEBUG : test_file.bak: Need to transfer - File not found at Destination
2025/01/03 13:56:04 DEBUG : test_file.bak: sha1 = 4e1243bd22c66e76c2ba9eddc1f91394e57f9f83 OK
2025/01/03 13:56:04 INFO : test_file.bak: Copied (new)
2025/01/03 13:56:04 INFO :
Transferred: 5 B / 5 B, 100%, 2 B/s, ETA 0s
Transferred: 1 / 1, 100%
Elapsed time: 9.4s
2025/01/03 13:56:04 DEBUG : 9 go routines active
Furthermore, I've found this, brief, reddit post: Input/Output error on one folder in proton drive?
That'd indicate Proton changed something on the 13th of December. Which could roughly be true, as similar errors as in my opening post containing "Dieser Wert sollte nicht leer sein." (This value should not be empty.) showed up in my logs from the 11th of December.