Cannot delete an imported read-only calendar

[jogojapan]

Steps to reproduce

1. Click on + ("add new calendar")
2. Enter the URL of a publicly available calendar that needs authentication [1]
3. Click "edit" calendar
4. Click on "delete" and confirm

[1] I suspect that Nextcloud Calendar does not support importing calendars that need authentication because it never asks for a password. Nevertheless, the system should deal with a user entering such a URL.

Expected behavior

The calendar should be removed from the list.

(Also, if calendars that require authentication are not supported, there should be an error message at time of adding, and the calendar should not have been added in the first place.)

Actual behavior

The calendar is struck through, but remains in the list. Upon refreshing the page, it is not even struck through anymore, and appears as a normal calendar.

Note: If this is related to the fact that calendars that require authentication are not supported, it should still be possible to delete them after erroneously adding them.

Calendar app version

6.5.2

CalDAV-clients used

No response

Browser

Vivaldi 8.1.4087.61 (based on Chromium 150.0.7871.214)

Client operating system

Fedora 44

Server operating system

Docker container running the Apache image

Web server

Apache

Database engine version

MariaDB

PHP engine version

Other

Nextcloud version

34.0.2

Updated from an older installed version or fresh install

No response

List of activated apps

Enabled:
  - activity: 7.0.0
  - admin_audit: 1.24.0
  - admincockpit: 1.3.4
  - app_api: 34.0.0
  - appstore: 1.0.0
  - assistant: 3.5.0
  - bruteforcesettings: 7.0.0
  - calendar: 6.5.2
  - circles: 34.0.0
  - cloud_federation_api: 1.18.0
  - comments: 1.24.0
  - contacts: 8.7.5
  - contactsinteraction: 1.15.0
  - context_chat: 5.4.0
  - dashboard: 7.14.0
  - dav: 1.39.0
  - end_to_end_encryption: 2.2.2
  - epubviewer: 1.9.7
  - external: 9.0.1
  - federatedfilesharing: 1.24.0
  - federation: 1.24.0
  - files: 2.6.0
  - files_automatedtagging: 5.0.0
  - files_downloadlimit: 5.2.0
  - files_lock: 34.0.1
  - files_pdfviewer: 7.0.0-dev.0
  - files_reminders: 1.7.0
  - files_sharing: 1.26.0
  - files_trashbin: 1.24.0
  - files_versions: 1.27.0
  - firstrunwizard: 7.0.0-dev.0
  - flow_notifications: 5.0.0
  - fulltextsearch: 34.0.1
  - gpxpod: 8.3.0
  - integration_github: 3.2.6
  - integration_google: 4.4.0
  - integration_immich: 1.4.0
  - integration_mastodon: 5.2.0
  - integration_openai: 4.5.2
  - integration_openstreetmap: 4.2.0
  - integration_paperless: 1.0.13
  - integration_peertube: 2.1.1
  - logreader: 7.0.0
  - lookup_server_connector: 1.22.0
  - mail: 5.10.11
  - nextcloud_announcements: 6.0.0
  - notes: 6.0.1
  - notifications: 7.0.0-dev.1
  - notify_push: 1.3.5
  - oauth2: 1.22.0
  - office: 1.0.0
  - oidc: 2.0.4
  - password_policy: 6.0.0-dev.0
  - phonetrack: 1.3.2
  - photos: 7.0.0
  - privacy: 6.0.0-dev.1
  - profile: 1.3.0
  - provisioning_api: 1.24.0
  - recommendations: 7.0.0
  - related_resources: 5.0.0-dev.0
  - richdocuments: 11.1.0
  - serverinfo: 6.0.0
  - settings: 1.17.0
  - sharebymail: 1.24.0
  - sociallogin: 6.5.4
  - spreed: 24.0.3
  - support: 6.0.0
  - survey_client: 6.0.0-dev.0
  - systemtags: 1.24.0
  - tasks: 0.18.1
  - text: 8.0.0
  - theming: 2.9.0
  - twofactor_backupcodes: 1.23.0
  - twofactor_nextcloud_notification: 8.0.0
  - twofactor_totp: 16.0.0
  - updatenotification: 1.24.0
  - uppush: 2.5.0
  - user_status: 1.14.0
  - viewer: 7.0.0-dev.0
  - weather_status: 1.14.0
  - webhook_listeners: 1.6.0
  - whiteboard: 1.5.9
  - workflowengine: 2.16.0
Disabled:
  - encryption: 2.22.0
  - files_external: 1.26.0
  - suspicious_login: 12.0.0-dev.0
  - user_ldap: 1.25.0

Nextcloud configuration

Web server error log

Log file

Browser log

Additional info

PHP engine info:
PHP 8.5.9 (cli) (built: Aug 5 2026 00:26:29) (NTS)
Copyright (c) The PHP Group
Built by https://github.com/docker-library/php
Zend Engine v4.5.9, Copyright (c) Zend Technologies
with Zend OPcache v8.5.9, Copyright (c), by Zend Technologies