[Bug]: Drag and Drop upload to subfolder works in Firefox but not Chrome based browser

[morticah]

⚠️ This issue respects the following points: ⚠️

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

Bug description

If I try to upload a file via drag and drop while dragging it to a folder icon it works from Firefox but not from Chromium/Chrome/Edge/Brave. On Chromium based browsers I get two times the message Unknown error during upload.

I tested it with anonymous accessed public folder and with folders of a normal logged in user.
I tested it on a Nextcloud-AIO-server and on a server based on the community maintained docker micro-image. Both behind an Nginx-reverse-proxy.
I'll report the specifics for the AIO-instance in this report.

Steps to reproduce

1. Create a folder in your nextcloud but don't enter/open it
2. Drag a file from your local drive to this folder in a chromium based browser
3. Icon of the Folder should change but no upload and the message Unknown error during upload should appear

Expected behavior

The icon for the folder should change, the upload progress should be on display, after successful upload the folder icon should change to normal.

Nextcloud Server version

33

Operating system

Debian/Ubuntu

PHP engine version

PHP 8.4

Web server

Apache (supported)

Database engine version

PostgreSQL

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

Updated from a MINOR version (ex. 32.0.1 to 32.0.2)

Are you using the Nextcloud Server Encryption module?

Encryption is Disabled

What user-backends are you using?

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

Configuration report

{
    "system": {
        "one-click-instance": true,
        "one-click-instance.user-limit": 100,
        "memcache.local": "\\OC\\Memcache\\APCu",
        "apps_paths": [
            {
                "path": "\/var\/www\/html\/apps",
                "url": "\/apps",
                "writable": false
            },
            {
                "path": "\/var\/www\/html\/custom_apps",
                "url": "\/custom_apps",
                "writable": true
            }
        ],
        "check_data_directory_permissions": false,
        "memcache.distributed": "\\OC\\Memcache\\Redis",
        "memcache.locking": "\\OC\\Memcache\\Redis",
        "redis": {
            "host": "***REMOVED SENSITIVE VALUE***",
            "password": "***REMOVED SENSITIVE VALUE***",
            "port": 6379
        },
        "overwritehost": "USERREMOVED",
        "overwriteprotocol": "https",
        "passwordsalt": "***REMOVED SENSITIVE VALUE***",
        "secret": "***REMOVED SENSITIVE VALUE***",
        "trusted_domains": [
            "localhost",
            "USERREMOVED"
        ],
        "datadirectory": "***REMOVED SENSITIVE VALUE***",
        "dbtype": "pgsql",
        "version": "33.0.2.2",
        "overwrite.cli.url": "https:\/\/USERREMOVED\/",
        "dbname": "***REMOVED SENSITIVE VALUE***",
        "dbhost": "***REMOVED SENSITIVE VALUE***",
        "dbport": "",
        "dbtableprefix": "oc_",
        "dbuser": "***REMOVED SENSITIVE VALUE***",
        "dbpassword": "***REMOVED SENSITIVE VALUE***",
        "installed": true,
        "instanceid": "***REMOVED SENSITIVE VALUE***",
        "maintenance": false,
        "updatedirectory": "\/nc-updater",
        "loglevel": 1,
        "log_type": "file",
        "logfile": "\/var\/www\/html\/data\/nextcloud.log",
        "log_rotate_size": 10485760,
        "log.condition": {
            "apps": [
                "admin_audit"
            ]
        },
        "preview_max_x": 2048,
        "preview_max_y": 2048,
        "jpeg_quality": 60,
        "enabledPreviewProviders": {
            "1": "OC\\Preview\\Image",
            "2": "OC\\Preview\\MarkDown",
            "3": "OC\\Preview\\MP3",
            "4": "OC\\Preview\\TXT",
            "5": "OC\\Preview\\OpenDocument",
            "6": "OC\\Preview\\Movie",
            "7": "OC\\Preview\\Krita",
            "0": "OC\\Preview\\Imaginary",
            "23": "OC\\Preview\\ImaginaryPDF"
        },
        "enable_previews": true,
        "upgrade.disable-web": true,
        "mail_smtpmode": "smtp",
        "trashbin_retention_obligation": "auto, 30",
        "versions_retention_obligation": "auto, 30",
        "activity_expire_days": 30,
        "simpleSignUpLink.shown": false,
        "share_folder": "\/Shared",
        "one-click-instance.link": "https:\/\/nextcloud.com\/all-in-one\/",
        "upgrade.cli-upgrade-link": "https:\/\/github.com\/nextcloud\/all-in-one\/discussions\/2726",
        "maintenance_window_start": 100,
        "allow_local_remote_servers": true,
        "davstorage.request_timeout": 3600,
        "htaccess.RewriteBase": "\/",
        "dbpersistent": false,
        "auth.bruteforce.protection.enabled": true,
        "ratelimit.protection.enabled": true,
        "files_external_allow_create_new_local": false,
        "trusted_proxies": "***REMOVED SENSITIVE VALUE***",
        "preview_imaginary_url": "***REMOVED SENSITIVE VALUE***",
        "preview_imaginary_key": "***REMOVED SENSITIVE VALUE***",
        "default_phone_region": "DE",
        "mail_sendmailmode": "smtp",
        "mail_from_address": "***REMOVED SENSITIVE VALUE***",
        "mail_domain": "***REMOVED SENSITIVE VALUE***",
        "mail_smtpauth": 1,
        "mail_smtphost": "***REMOVED SENSITIVE VALUE***",
        "mail_smtpport": "587",
        "mail_smtpname": "***REMOVED SENSITIVE VALUE***",
        "mail_smtppassword": "***REMOVED SENSITIVE VALUE***",
        "documentation_url.server_logs": "https:\/\/github.com\/nextcloud\/all-in-one\/discussions\/5425",
        "updatechecker": true,
        "updater.release.channel": "stable",
        "app_install_overwrite": [
            "nextcloud-aio"
        ],
        "DOMAIN": "USERREMOVED",
        "AIO_VERSION": "v12.9.2"
    }
}

List of activated Apps

Enabled:
  - activity: 6.0.0
  - admin_audit: 1.23.0
  - bruteforcesettings: 6.0.0
  - calendar: 6.3.0-rc.1
  - cloud_federation_api: 1.17.0
  - contacts: 8.4.5
  - cookbook: 0.11.6
  - dav: 1.36.0
  - federatedfilesharing: 1.23.0
  - files: 2.5.0
  - files_downloadlimit: 5.1.0
  - files_pdfviewer: 6.0.0
  - files_reminders: 1.6.0
  - files_sharing: 1.25.2
  - files_trashbin: 1.23.0
  - files_versions: 1.26.0
  - firstrunwizard: 6.0.0
  - gpoddersync: 3.16.0
  - logreader: 6.0.0
  - lookup_server_connector: 1.21.0
  - nextcloud-aio: 0.8.0
  - nextcloud_announcements: 5.0.0
  - notes: 5.0.0
  - notifications: 6.0.0
  - notify_push: 1.3.1
  - oauth2: 1.21.0
  - password_policy: 5.0.0
  - photos: 6.0.0
  - privacy: 5.0.0
  - profile: 1.2.0
  - provisioning_api: 1.23.0
  - serverinfo: 5.0.0
  - settings: 1.16.0
  - sharebymail: 1.23.0
  - support: 5.0.0
  - tasks: 0.17.1
  - text: 7.0.0
  - theming: 2.8.0
  - twofactor_backupcodes: 1.22.0
  - twofactor_totp: 15.0.0
  - updatenotification: 1.23.0
  - user_status: 1.13.0
  - viewer: 6.0.0
  - webhook_listeners: 1.5.0
  - workflowengine: 2.15.0
Disabled:
  - app_api: 33.0.0 (installed 4.0.0)
  - circles: 33.0.0 (installed 30.0.0-dev)
  - comments: 1.23.0 (installed 1.20.1)
  - contactsinteraction: 1.14.1 (installed 1.11.0)
  - dashboard: 7.13.0 (installed 7.10.0)
  - encryption: 2.21.0
  - federation: 1.23.0 (installed 1.20.0)
  - files_external: 1.25.1
  - recommendations: 6.0.0 (installed 3.0.0)
  - related_resources: 4.0.0 (installed 1.5.0)
  - survey_client: 5.0.0 (installed 2.0.0)
  - suspicious_login: 11.0.0
  - systemtags: 1.23.0 (installed 1.20.0)
  - testing: 1.23.0
  - twofactor_nextcloud_notification: 7.0.0
  - user_ldap: 1.24.0
  - weather_status: 1.13.0 (installed 1.10.0)

Nextcloud Signing status

No errors have been found.

Nextcloud Logs

There are no relating log entries generated in the nextcloud.log

These are the entries I see in the nginx-access-logs on the reverse proxy:
192.168.5.153 - - [04/May/2026:14:18:36 +0200] "PROPFIND /public.php/dav/files/XTXwM7JCbQDYNis/test/ HTTP/2.0" 207 1457 "-" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/147.0.0.0 Safari/537.36"
192.168.5.153 - - [04/May/2026:14:18:36 +0200] "MKCOL /public.php/dav/uploads/XTXwM7JCbQDYNis/web-file-upload-cb2c578024741252 HTTP/2.0" 201 0 "-" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/147.0.0.0 Safari/537.36"
192.168.5.153 - - [04/May/2026:14:18:36 +0200] "DELETE /public.php/dav/uploads/XTXwM7JCbQDYNis/web-file-upload-cb2c578024741252 HTTP/2.0" 204 0 "-" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/147.0.0.0 Safari/537.36"

Additional info

Problem was first observed with 33.0.2 but persists in 33.0.3