[Bug]: `Failed to open stream` + `Error while running background job` immediately after installation

[Adspectus]

⚠️ This issue respects the following points: ⚠️

• [X] This is a bug, not a question or a configuration/webserver/proxy issue.
• [X] This issue is not already reported on Github OR Nextcloud Community Forum (I've searched it).
• [X] Nextcloud Server is up to date. See Maintenance and Release Schedule for supported versions.
• [X] I agree to follow Nextcloud's Code of Conduct.

Bug description

After installation and first start on Nextcloud AIO I see the following message in the overview of systemadministration: 2 errors in protocols. When I click on protocols I can see the following:

{
  "reqId": "5rgiLEkUnGJYuN36W5Kj",
  "level": 3,
  "time": "2024-06-01T13:32:58+00:00",
  "remoteAddr": "",
  "user": "admin",
  "app": "PHP",
  "method": "",
  "url": "--",
  "message": "fopen(/var/www/html/config/config.php): Failed to open stream: No such file or directory at /var/www/html/lib/private/Config.php#225",
  "userAgent": "--",
  "version": "28.0.5.1",
  "data": {
    "app": "PHP"
  },
  "id": "665b3280372d1"
}

And:

{
  "reqId": "Qd07Vbl2vOSYyNbf3sw2",
  "level": 3,
  "time": "2024-06-01T13:33:47+00:00",
  "remoteAddr": "",
  "user": "--",
  "app": "core",
  "method": "",
  "url": "--",
  "message": "Error while running background job (class: OCA\\Theming\\Jobs\\MigrateBackgroundImages, arguments: Array\n(\n    [stage] => prepare\n)\n)",
  "userAgent": "--",
  "version": "28.0.5.1",
  "exception": {
    "Exception": "OCP\\Files\\NotFoundException",
    "Message": "/appdata_octtordoeggb/theming/global",
    "Code": 0,
    "Trace": [
      {
        "file": "/var/www/html/lib/private/Files/Node/LazyFolder.php",
        "line": 161,
        "function": "get",
        "class": "OC\\Files\\Node\\Root",
        "type": "->",
        "args": [
          "/appdata_octtordoeggb/theming/global"
        ]
      },
      {
        "file": "/var/www/html/lib/private/Files/AppData/AppData.php",
        "line": 132,
        "function": "get",
        "class": "OC\\Files\\Node\\LazyFolder",
        "type": "->",
        "args": [
          "appdata_octtordoeggb/theming/global"
        ]
      },
      {
        "file": "/var/www/html/apps/theming/lib/Jobs/MigrateBackgroundImages.php",
        "line": 168,
        "function": "getFolder",
        "class": "OC\\Files\\AppData\\AppData",
        "type": "->",
        "args": [
          "global"
        ]
      },
      {
        "file": "/var/www/html/apps/theming/lib/Jobs/MigrateBackgroundImages.php",
        "line": 100,
        "function": "storeUserIdsToProcess",
        "class": "OCA\\Theming\\Jobs\\MigrateBackgroundImages",
        "type": "->",
        "args": [
          []
        ]
      },
      {
        "file": "/var/www/html/apps/theming/lib/Jobs/MigrateBackgroundImages.php",
        "line": 79,
        "function": "runPreparation",
        "class": "OCA\\Theming\\Jobs\\MigrateBackgroundImages",
        "type": "->",
        "args": []
      },
      {
        "file": "/var/www/html/lib/public/BackgroundJob/Job.php",
        "line": 81,
        "function": "run",
        "class": "OCA\\Theming\\Jobs\\MigrateBackgroundImages",
        "type": "->",
        "args": [
          [
            "prepare"
          ]
        ]
      },
      {
        "file": "/var/www/html/lib/public/BackgroundJob/QueuedJob.php",
        "line": 57,
        "function": "start",
        "class": "OCP\\BackgroundJob\\Job",
        "type": "->",
        "args": [
          [
            "OC\\BackgroundJob\\JobList"
          ]
        ]
      },
      {
        "file": "/var/www/html/lib/public/BackgroundJob/QueuedJob.php",
        "line": 47,
        "function": "start",
        "class": "OCP\\BackgroundJob\\QueuedJob",
        "type": "->",
        "args": [
          [
            "OC\\BackgroundJob\\JobList"
          ]
        ]
      },
      {
        "file": "/var/www/html/cron.php",
        "line": 152,
        "function": "execute",
        "class": "OCP\\BackgroundJob\\QueuedJob",
        "type": "->",
        "args": [
          [
            "OC\\BackgroundJob\\JobList"
          ],
          [
            "OC\\Log"
          ]
        ]
      }
    ],
    "File": "/var/www/html/lib/private/Files/Node/Root.php",
    "Line": 207,
    "message": "Error while running background job (class: OCA\\Theming\\Jobs\\MigrateBackgroundImages, arguments: Array\n(\n    [stage] => prepare\n)\n)",
    "exception": [],
    "CustomMessage": "Error while running background job (class: OCA\\Theming\\Jobs\\MigrateBackgroundImages, arguments: Array\n(\n    [stage] => prepare\n)\n)"
  },
  "id": "665b3280372bf"
}

Steps to reproduce

1. Install Nextcloud AIO according to the guide in this repo using Apache httpd as reverse proxy
2. Open Nextcloud Admin-Settings the overview shows 2 errors related to system configuration
3. Checking the protocol shows the entries documented above

Expected behavior

No errors in protocol after installation.

Installation method

Official All-in-One appliance

Nextcloud Server version

28

Operating system

Other

PHP engine version

PHP 8.2

Web server

Apache (supported)

Database engine version

PostgreSQL

Is this bug present after an update or on a fresh install?

Fresh Nextcloud Server install

Are you using the Nextcloud Server Encryption module?

Encryption is Disabled

What user-backends are you using?

• [X] Default user-backend (database)
• [ ] LDAP/ Active Directory
• [ ] SSO - SAML
• [ ] Other

Configuration report

No response

List of activated Apps

No response

Nextcloud Signing status

No response

Nextcloud Logs

No response

Additional info

OS: Linux 6.6.28+rpt-rpi-2712 aarch64

[joshtrichards]

You're not getting these repeatedly though, correct?

[Adspectus]

No, only after installing.