[Bug]: PDFs do not load with secure view enabled

[Vito0912]

Describe the bug
When secure view is enabled with tagging restrictions, any PDFs assigned with the tag become completely inaccessible. The OnlyOffice editor does not even try to open

Edit: It does not work when clicking on it directly. When I open it with Office, it works correctly. Sadly, this is not a solution, because shares with a download option still have this issue. If I remove download from the share, it opens in Office and works. As soon as I add download permission, it tries to open in the normal PDF viewer and fails again.

To Reproduce
Steps to reproduce the behavior:

1. Enable secure view

2. Try to open an PDF file

Expected behavior
Either the PDF opens normally (or better, I am not sure if PDFs are supported) show the PDF as secure view

Screenshots
If applicable, add screenshots to help explain your problem.

Client details:

• OS: Windows
• Browser Firefox
• Version 144.0b5
• Device: Desktop

Server details

Operating system: Linux on Docker. AIO managed

Web server: /

Database: /

PHP version: /

Nextcloud version: 31.0.9

Version of the richdocuments app 8.7.5

Version of Collabora Online 25.04.5.2

Configuration of the richdocuments app

"apps": {
        "richdocuments": {
            "installed_version": "8.7.5",
            "enabled": "yes",
            "types": "filesystem,prevent_group_restriction",
            "canonical_webroot": "",
            "public_wopi_url": "https://<domain>",
            "external_apps": "",
            "wopi_allowlist": "<>",
            "wopi_callback_url": "http:\/\/nextcloud-aio-apache:<port>",
            "wopi_url": "http:\/\/nextcloud-aio-apache:<port>",
            "disable_certificate_verification": ""
        }
    }

Logs

Nextcloud log (data/nextcloud.log)

None for this

Browser log

Uncaught (in promise) SyntaxError: JSON.parse: unexpected character at line 1 column 1 of the JSON data

Uncaught (in promise) SyntaxError: JSON.parse: unexpected character at line 1 column 1 of the JSON data

XHRGET
https://<file path>
[HTTP/2 403  144ms]

Uncaught (in promise) SyntaxError: JSON.parse: unexpected character at line 1 column 1 of the JSON data

[blizzz]

It is a feature, not a bug. ™️

They are intended to be considered and treated as such, they were not and it was fixed with #4891