Error while Zipping when root folder is read only: `No create permission for path`

Just tried the app and I got the following issue:

{
  "reqId": "ddnrK6weTbpLI0qMPo7o",
  "level": 3,
  "time": "2021-11-19T00:55:02+01:00",
  "remoteAddr": "",
  "user": "--",
  "app": "files_zip",
  "method": "",
  "url": "--",
  "message": "Failed to create zip archive",
  "userAgent": "--",
  "version": "22.2.3.0",
  "exception": {
    "Exception": "OCP\\Files\\NotPermittedException",
    "Message": "No create permission for path",
    "Code": 0,
    "Trace": [
      {
        "file": "/var/www/nextcloud/apps/files_zip/lib/Service/ZipService.php",
        "line": 92,
        "function": "newFile",
        "class": "OC\\Files\\Node\\Folder",
        "type": "->"
      },
      {
        "file": "/var/www/nextcloud/apps/files_zip/lib/BackgroundJob/ZipJob.php",
        "line": 65,
        "function": "zip",
        "class": "OCA\\FilesZip\\Service\\ZipService",
        "type": "->"
      },
      {
        "file": "/var/www/nextcloud/lib/public/BackgroundJob/Job.php",
        "line": 79,
        "function": "run",
        "class": "OCA\\FilesZip\\BackgroundJob\\ZipJob",
        "type": "->"
      },
      {
        "file": "/var/www/nextcloud/lib/public/BackgroundJob/QueuedJob.php",
        "line": 47,
        "function": "execute",
        "class": "OCP\\BackgroundJob\\Job",
        "type": "->"
      },
      {
        "file": "/var/www/nextcloud/cron.php",
        "line": 127,
        "function": "execute",
        "class": "OCP\\BackgroundJob\\QueuedJob",
        "type": "->"
      }
    ],
    "File": "/var/www/nextcloud/lib/private/Files/Node/Folder.php",
    "Line": 209,
    "CustomMessage": "Failed to create zip archive"
  },
  "id": "6196e81a535c6"
}

It has most likely the same reason why https://github.com/nextcloud/server/issues/25787 happened.

Start with lib/Service/ZipService.php at line 92, where the trace shows newFile failing, then follow the call from lib/BackgroundJob/ZipJob.php line 65. Reproduce zipping with a read-only root folder and verify that the archive is created successfully without the “No create permission for path” error.