[bug] Disabling OnlyOffice plugin breaks office document downloads

[gvengel]

Description of the bug

If you disable the OnlyOffice plugin via the admin UI, associated files open to a blank page instead of the default "download" page.

Step by step instructions to reproduce the bug

• Navigate to /admin/settings
• Under Features -> Office, uncheck Enable
• Navigate to /.
• Browse to an office document (.doc, .xls, etc)

Can you replicate that error from the demo?

No, reproducing requires admin access to disable the OnlyOffice plugin.

Observed behavior

Opening the office document will return a blank page.

Expected behavior

Opening the office document should return the download page.