PDF preview impossible in modern Zimbra

[sturpin]

Hi @wangen

We were discussing this exact thing here

PDF preview not possible in Zimbra Pro

On my Zimbra Pro OVHcloud mailbox, the preview of PDF attachments fails with the message “Unable to load preview”. The problem occurs on Windows, Android, macOS and iPhone/iPad, including in webmail. By contrast, image‑format attachments display correctly. PDFs can be downloaded and opened on the computer. The issue therefore appears to be specific to PDF preview.